Genetic analysis of a patient with familial hypercholesterolemia due to variant of LDLR gene / 中华医学遗传学杂志

OBJECTIVE@#To analyze variant of LDLR gene in a patient with familial hypercholesterolemia (FH) in order to provide a basis for the clinical diagnosis and genetic counseling.@*METHODS@#A patient who had visited the Reproductive Medicine Center of the First Affiliated Hospital of Anhui Medical University in June 2020 was selected as the study subject. Clinical data of the patient was collected. Whole exome sequencing (WES) was applied to the patient. Candidate variant was verified by Sanger sequencing. Conservation of the variant site was analyzed by searching the UCSC database.@*RESULTS@#The total cholesterol level of the patient was increased, especially low density lipoprotein cholesterol. A heterozygous c.2344A>T (p.Lys782*) variant was detected in the LDLR gene. Sanger sequencing confirmed that the variant was inherited from the father.@*CONCLUSION@#The heterozygous c.2344A>T (p.Lys782*) variant of the LDLR gene probably underlay the FH in this patient. Above finding has provided a basis for genetic counseling and prenatal diagnosis for this family.

Impact of orthotopic liver transplantation on serum lipid level and growing development in patients with homozygous or compound heterozygous familial hypercholesterolemia / 中华心血管病杂志

Objective: To investigate the impact of orthotopic liver transplantation on serum lipid and growing development in patients with homozygous (HoFH) or compound heterozygotes (cHeFH) familial hypercholesterolemia. Methods: Patients who were treated in Peking Union Medical College Hospital from August 2019 to August 2021, entered the rare disease database and underwent liver transplantation, were included in this single center retrospective cohort study. The height for age Z score (HAZ) and length for age Z score (WAZ) at birth, at the time of transplantation and one year after transplantation were calculated respectively by collecting demographic characteristics, clinical manifestations, echocardiography, lipid-lowering treatment, blood lipid level data and donor characteristics data of liver transplantation. The serum cholesterol level and growing development changes before and after liver transplantation were evaluated. Results: A total of five patients with HoFH or cHeFH, including two females, were included in this study. The median age was 10 years (6-22 years). The median follow up duration was 28 months (24-33 months). All HoFH or cHeFH patients in this study received the maximum daily dosage of the lipid-lowering drug combined with low salt and low-fat diet control treatment for at least 3 months before orthotopic liver transplantation. The average level of total cholesterol (TC) decreased by 27% compared with that before treatment, the level of low-density lipoprotein cholesterol (LDL-C) decreased by 21% after 3 months treatment. There was no intervention of lipid-lowering therapy after operation. One month after liver transplantation, the average levels of TC and LDL-C further decreased rapidly by 68% and 76% respectively. One year after liver transplantation, the level of LDL-C decreased from (17.1±1.6)mmol/L without any intervention before transplantation to (3.0±0.7)mmol/L, and remained stable thereafter. In addition, compared with no intervention before liver transplantation, the serum triglyceride (TG) level decreased after the maximum daily dosage of the lipid-lowering drug and low salt and low-fat diet control for 3 months ((1.88±0.27) mmol/L vs. (1.12±0.55)mmol/L, P=0.031), and the HDL-C level also decreased significantly ((1.95±0.49)mmol/L vs. (0.95±0.30)mmol/L, P=0.006) at the same time period. TG and HDL-C remained stable after liver transplantation during the 24-month follow-up period (P>0.05). One and two years after liver transplantation, there was no significant difference in height and weight, malnutrition and growth retardation between the patients in this cohort and Chinese children of the same age. Conclusion: Early liver transplantation is a feasible and effective treatment option for HoFH or cHeFH patients with extremely high serum low-density lipoprotein cholesterol levels.

Identification and 3D architecture analysis of the LIPC gene mutation in a pedigree with familial hypercholesterolemia-like phenotype / 中华心血管病杂志

Objective: To identify and analyze 3D architecture of the mutational sites of susceptible genes in a pedigree with familial hypercholesterolemia-like phenotype (FHLP). Methods: This is a case series study. A pedigree with suspected familial hypercholesterolemia was surveyed. The proband admitted in Beijing Anzhen Hospital in April 2019. Whole-exome sequencing was performed to determine the mutational sites of susceptible genes in the proband. Polymerase chain reaction (PCR) sequencing was used to verify the pathogenic variant on proband's relatives. The structural and functional changes of the proteins were analyzed and predicted by Discovery Studio 4.0 and PyMol 2.0. Results: The patients in the pedigree showed abnormal lipid profiles, especially elevated levels of total cholesterol(TC). The genetic screening detected the c.1330C>T SNP in the exon 8 of lipase C (LIPC) gene, this mutation leads to an amino acid substitution from arginine to cysteine at position 444 (Arg444Cys), in the proband and proband's father and brother. In this family, members with this mutation exhibited elevated TC, whereas lipid profile was normal from the proband's mother without this mutation. This finding indicated that LIPC: c.1330C>T mutation might be the mutational sites of susceptible genes. The analysis showed that Arg444Cys predominantly affected the ligand-binding property of the protein, but had a limited impact on catalytic function. Conclusion: LIPC: c.1330C>T is a new mutational site of susceptible genes in this FHLP pedigree.

Advances in diagnosis and treatment of familial hypercholesterolemia / 南方医科大学学报

Familial hypercholesterolemia (FH) is an autosomal dominant inherited disease caused by abnormal lipoprotein metabolism. Patients with FH have a significantly increased risk of coronary artery disease (CAD) due to long-term exposure to high levels of low-density lipoprotein (LDL). The diagnosis of FH relies heavily on gene detection, and examination of LDL receptor (LDLR) function is of great significance in its treatment. This review summarizes the current advances in the screening, diagnosis, and treatment of FH and functional analysis of LDLR gene mutations.

Criterios predictores en el diagnóstico de la hipercolesterolemia familiar / Predictive criteria in the diagnosis of familial hypercholesterolemia

Introducción: La hipercolesterolemia familiar es una enfermedad con alta prevalencia, no tratada acorta la esperanza de vida, por lo que el diagnóstico a edades tempranas resulta fundamental. Las pruebas genéticas constituyen el gold standard para el diagnóstico de hipercolesterolemia familiar, sin embargo, la no disponibilidad del test genético no debe constituir un impedimento para la adecuada conducta en estos casos. Objetivo: Identificar criterios clínicos predictores en el diagnóstico por pesquisa de la hipercolesterolemia familiar. Métodos: Se realizó un estudio descriptivo prospectivo a partir de una muestra de 393 pacientes (casos índices) de HF en el Hospital Clínico Quirúrgico Hermanos Ameijeiras; durante el período 2008-2018. Resultados: En la pesquisa familiar fueron identificados 177 (15,66 por ciento) nuevos casos de hipercolesterolemia familiar, de ellos se clasifican como casos positivos 35 (19,77 por ciento), casos probables 58 (32,77 por ciento) y casos posibles 84 (47,46 por ciento). Las categorías del estrato Make early diagnosis to prevent early death MEDPED y la edad del caso índice resultaron ser las variables clínicas de interés con mayor probabilidad para identificar nuevos casos de hipercolesterolemia familiar. Conclusiones: los criterios clínicos estandarizados de la escala make early diagnosis to prevent early death P y la edad del caso índice resultaron ser indicadores predictivos de gran valor para identificar y estratificar casos con variantes fenotípicas de hipercolesterolemia familiar(AU)

Introduction: Familial hypercholesterolemia is a disease with high prevalence; it shortens life expectancy if it is not treated, so early diagnosis is essential. Genetic tests are the gold standard for the diagnosis of familial hypercholesterolemia, however, the unavailability of the genetic test should not be an obstacle to proper conduct in these cases. Objective: To identify predictive clinical criteria in the diagnosis by screening of familial hypercholesterolemia. Methods: A prospective descriptive study was carried out from a sample of 393 patients (index cases) of FH at Hermanos Ameijeiras Surgical Clinical Hospital from 2008 to 2018. Results: In the family investigation, 177 (15.66 percent) new cases of familial hypercholesterolemia were identified, 35 of them (19.77 percent) are classified as positive cases, 58 (32.77 percent) as probable cases and 84 as possible cases (47.46 percent)The stratum categories of Make Early Diagnosis to Prevent Early Death (MEDPED) and the age of the index case turned out to be the clinical variables of interest with the greatest probability to identify new cases of familial hypercholesterolemia. Conclusions: The standardized clinical criteria of the make early diagnosis to prevent early death P scale and the age of the index case turned out to be highly valuable predictive indicators to identify and stratify cases with phenotypic variants of familial hypercholesterolemia(AU)

Avaliação do perfil de microRNAs exossomais em portadores de hipercolesterolemia familial / Evaluation of the profile of exosomal microRNAs in patients with familial hypercholesterolemia

A Hipercolesterolemia Familial (HF) é uma doença hereditária do metabolismo lipídico que causa aos portadores alta incidência de aterosclerose prematura. A HF pode ser diagnosticada clínica e geneticamente, entretanto, apenas cerca de 40% podem ter confirmados pelo diagnostico molecular. Assim, outros sistemas de diagnóstico devem ser avaliados. Ultimamente devido a estabilidade em fluidos biológicos, os exossomos circulantes apresentam grande potencial, pois carreiam um número variado de compostos e são considerados veículos de intercomunicação entre os tecidos. Sabe-se que vários RNAs são carreados nos exossomos, incluindo miRNAs, lncRNA e uma variedade de proteínas. Estes componentes podem ser marcadores de diagnóstico para várias doenças inclusive a HF e suas complicações cardiovasculares. Foram utilizadas amostras de exossomos plasmáticos provenientes de 54 pacientes HF sem uso de estatina por, no mínimo, seis semanas, e 38 indivíduos normolipidêmicos para sequenciamento de miRNAs e estudo da proteômica. Os exossomos foram isolados utilizando dois métodos precipitação química e cromatográfica de exclusão de tamanho e caraterizados utilizando: dispersão de luz dinâmica, Western blotting, rastreamento de nanopartículas (NanoSight), imunomarcação e microscopia eletrônica de transmissão. Os miRNAs e proteínas foram extraídos dos exossomos e analisados por sequenciamento de nova geração e espectrometria de massa, respectivamente. Os dados clínicos, biodemográficos e laboratoriais dos pacientes HF e controles indicaram diferenças significativas esperadas entre os grupos, indicando que foram selecionados adequadamente. A caracterização físico-química dos exossomos mostrou resultados com tamanho de ˜90nm e imunorreação positiva para tetraspaninas. O resultado do sequenciamento identificou acima 2000 miRNAs. Os miR-122- 5p e miR-21-5p apresentaram expressão aumentada no grupo HF (log2FC=1,79 e log2FC=1,27, respectivamente), e o miR-122-5p pós normalização em relação ao controle manteve significativo comparados ao controle (p=0,034). A análise comparativa entre exossomos e plasma total mostrou diferença significativa, pois foram identificadas 239 proteínas (p <0,05) diferentes entre exossomos e plasma. Em exossomos, 17 proteínas foram aumentadas e 21 diminuídas em pacientes com HF em comparação com o controle (p <0,05). Destas, seis proteínas foram mais abundantes em HF e sete proteínas foram menos abundantes em exossomos de pacientes com HF em comparação com o controle. A análise de enriquecimento por bioinformática mostrou que a maior parte dessas moléculas (miRNAs e proteínas) foram relacionadas com metabolismo lipídico, dislipidemia, aterosclerose, doença arterial coronariana, adipogênese. Assim, na busca de novos alvos como potenciais biomarcadores de diagnóstico da HF, nossos resultados da análise integrativa entre os miRNAs e as proteínas exossomais abre novas frentes de pesquisa mais bem direcionadas, para a validação desses miRNAs e proteínas exossomais

Familial Hypercholesterolemia (FH) is an inherited disease of lipid metabolism that causes a high incidence of premature atherosclerosis in patients. FH can be diagnosed clinically and genetically, however, only about 40% can be confirmed by molecular diagnosis. Thus, other diagnostic systems should be evaluated. Lately, due to stability in biological fluids, circulating exosomes have great potential, as they carry a varied number of compounds and are considered vehicles of intercommunication between tissues. Several RNAs are known to be carried on exosomes, including miRNAs, lncRNA, and a variety of proteins. These components can be diagnostic markers for several diseases including FH and its cardiovascular complications. Plasma exosome samples from 54 FH patients without statin use for at least six weeks and 38 normolipidemic individuals were used for miRNA sequencing and proteomics studies. Exosomes were isolated using two methods chemical precipitation and size exclusion chromatography and characterized using: dynamic light scattering, Western blotting, nanoparticle tracking (NanoSight), immunostaining and transmission electron microscopy. MiRNAs and proteins were extracted from exosomes and analyzed by next-generation sequencing and mass spectrometry, respectively. Clinical, biodemographic and laboratory data of FH patients and controls indicated significant expected differences between the groups, indicating that they were appropriately selected. The physicochemical characterization of exosomes showed results with a size of ˜90nm and positive immunoreaction for tetraspanins. The sequencing result identified above 2000 miRNAs. miR-122-5p and miR-21-5p showed increased expression in the FH group (log2FC=1.79 and log2FC=1.27, respectively), and miR122-5p after normalization in relation to the control remained significant compared to the control (p=0.034). The comparative analysis between exosomes and total plasma showed a significant difference, as 239 different proteins (p < 0.05) were identified between exosome and plasma. In exosomes, 17 proteins were increased and 21 decreased in FH patients compared to control (p < 0.05). Of these, six proteins were more abundant in FH and seven proteins were less abundant in exosomes from patients with FH compared to the control. Bioinformatics enrichment analysis showed that most of these molecules (miRNAs and proteins) were related to lipid metabolism, dyslipidemia, atherosclerosis, coronary artery disease, adipogenesis. Thus, in the search for new targets as potential diagnostic biomarkers of FH, our results of the integrative analysis between miRNAs and exosomal proteins opens new and better-directed research fronts for the validation of these miRNAs and exosomal proteins

Avaliação do perfil de metilação dos genes LDLR, PCSK9, LDLRAP1 em pacientes portadores de hipercolesterolemia familial / Evaluation of the methylation profile of LDLR, PCSK9, LDLRAP1 genes in patients with familial hypercholesterolemia

As variabilidades genotípicas que determinam algumas alterações fenotípicas e metabólicas podem ter seu diagnostico falho se baseado apenas nos dados genômicos. Na hipercolesterolemia familial (HF) pode-se observar que os dados de variantes nos genes da LDLR, PCSK9, APOB e LDLRAP1 sugeridos pelos consensos atuais para confirmar o diagnóstico, tem mostrado serem insuficientes, mostrando baixa porcentagem de confirmação, mesmo nos dos casos em que características fenotípicas apresentam dados sugestivos importantes. A complementação no auxílio diagnóstico com dados epigenéticos tem sido sugerida em muitas doenças, principalmente nas crônicos degenerativos. A metilação do DNA pode estar envolvida no mecanismo que regulam vários processos metabólicos, entre os quais os envolvidos na expressão de proteínas e neste estudo os que estão envolvidos no metabolismo do colesterol, que poderia explicar fenótipos hipercolesterolemicos sem demonstração clara de variantes nos genes de consenso. O objetivo do presente estudo foi comparar o perfil de metilação dos genes LDLR, PCSK9 e LDLRAP1 entre pacientes com diagnóstico de Hipercolesterolemia Familial confirmado através de variantes genéticas descritas na literatura e pacientes sem diagnóstico confirmado. Além da comparação com indíviduos normolipidêmicos. A seleção dos indivíduos foi realizada na Seção de Dislipidemia do Instituto Dante Pazzanese de Cardiologia (IDPC), do Departamento de Análises Clínicas e Toxicológicas da Universidade Federal do Rio Grande do Norte (UFRN), da Universidade Estadual de Campinas (UNICAMP) e da Faculdade de Medicina de São José do Rio Preto (FAMERP). Através dos critérios MEDPED foram selecionados 133 pacientes para a realização do sequenciamento de um painel de genes relacionados ao fenótipo de HF e a homeostasia do colesterol a fim de confirmar o diagnóstico. Todos os pacientes tiveram o DNA purificado, que foi submetido ao tratamento com bissulfito, amplificado, purificado, desnaturado e sequenciado no sistema PyroMark Q24. Avaliou-se o perfil de metilação, em sítio CpG dos genes da LDLR, PCSK9 e LDLR AP1. A análise estatística foi realizada utilizando o software SPSS v.19, GraphPad Prism, versão 1.03 e o e o software R. 4.1.0. Os pacientes foram classificados em Grupo I: Pacientes com diagnóstico molecular confirmado pelo estudo fenotípico e genotipico (n=40); Grupo II: Pacientes fenotipicamente determinados como hipercolesterolemico, mas sem diagnóstico molecular confirmado pelo estudo genomico (n=93); Grupo III: indivíduos fenotipicamente determinados normolipidêmicos de acordo com a V Diretriz Brasileira de Dislipidemia (n=23). A análise comparativa entre os grupos I x II e II x III, demonstrou diferença estatísta significativa em 13 sítios CpG do total de 28 sítios CpG analisados nos três genes. Além disso, foi possível concluir que alterações nos sítios CpG presentes no gene LDLR influenciaram na presença de xantomas e arco córneo. Houve correlação positiva entre a idade e perfil de metilação do gene PCSK9, assim como, alterações nos sítios CpG deste gene influenciaram na presença de arco córneo e IAM. Além disso, alterações no sítio CPG presente no gene LDLRAP1 influenciou no desenvolvimento de DAC, IAM e RM, além da presença de xantelasma

The genotypic variabilities that determine some phenotypic and metabolic alterations can be misdiagnosed if based only on genomic data. In familial hypercholesterolemia (FH) it can be observed that the data of variants in the genes of LDLR, PCSK9, APOB and LDLR AP1 suggested by the current consensus to confirm the diagnosis, has shown to be insufficient, showing a low percentage of confirmation, even in the cases in which phenotypic characteristics present important suggestive data. Complementing the diagnostic aid with epigenetic data has been suggested in many diseases, especially in chronic degenerative diseases. DNA methylation may be involved in the mechanisms that regulate several metabolic processes, including those involved in the expression of proteins that ,in this study, are involved in cholesterol metabolism, which could explain hypercholesterolemic phenotypes without a clear demonstration of variants in consensus genes. The aim of the present study was to compare the methylation profile of LDLR, PCSK9 and LDLRAP1 genes between patients with a diagnosis of Familial Hypercholesterolemia confirmed through genetic variants described in the literature and patients without a confirmed diagnosis. In addition to the comparison with normolipidemic individuals. The selection of individuals was carried out at the Dyslipidemia Section of the Instituto Dante Pazzanese de Cardiologia (IDPC), in the Department of Clinical and Toxicological Analyzes of the Federal University of Rio Grande do Norte (UFRN), in the State University of Campinas (UNICAMP) and in the Faculdade of Medicine of São José do Rio Preto (FAMERP). Through the MEDPED criteria, 133 patients were selected to perform the sequencing of a panel of genes related to the FH phenotype and cholesterol homeostasis in order to confirm the diagnosis. All patients had their DNA purified, which were subjected to bisulfite treatment, amplified, purified, denatured and sequenced on the PyroMark Q24 system. The methylation profile in the CpG site of the LDLR, PCSK9 and LDLRAP1 genes were evaluated. Statistical analysis were performed using SPSS v.19 software, GraphPad Prism, version 1.03 and R. 4.1.0 software. Patients were classified into Group I: Patients with a molecular diagnosis confirmed by phenotypic and genotypic studies (n=40); Group II: Patients phenotypically determined to be hypercholesterolemic, but without a molecular diagnosis confirmed by the genomic study (n=93); Group III: phenotypically determined normolipidemic individuals according to the V Brazilian Dyslipidemia Directive (n=23). The comparative analysis between groups I x II and II x III showed a statistically significant difference in 13 CpG sites of the total of 28 CpG sites analyzed in the three genes of the project. Furthermore, it was possible to conclude that alterations in the CpG sites present in the LDLR gene influenced the presence of xanthomas and arc corneum. There was a positive correlation between age and PCSK9 gene methylation profile, as well as changes in the CpG sites of this gene influenced the presence of arc corneum and AMI. In addition, alterations in the site present in the LDLRAP1 gene are influencing the development of CAD, AMI and MR, in addition to the presence of xanthelasma

Lipoprotein apheresis in patients with familial hypercholesterolemia: a single center research / 中华心血管病杂志

Objective: We evaluated the safety and efficacy of lipoprotein apheresis (LA) in patients with familial hypercholesterolemia (FH) who can't reach low-density lipoprotein cholesterol(LDL-C) target goals with the maximal tolerated dose of lipid-lowering agents. Methods: This was a retrospective cross-sectional study. Between February 2015 and November 2019, patients with FH who were admitted in Fuwai hospital and treated with LA were consecutively enrolled. Based on intensive lipid-lowering agents, these patients received LA by double filtration plasma pheresis (DFPP) method. The changes of lipid levels such as LDL-C and lipoprotein(a)[Lp(a)] were compared before and after LA treatment, and the changes of immunoglobulin (Ig) concentration and LA-related adverse effects were also discussed. Results: A total of 115 patients with FH were enrolled in this study, of which 8 cases were homozygous FH and 107 cases were heterozygous FH. The age was (43.9±12.2) years and there were 75 (65.2%) males, and 108 (93.8%) with coronary artery disease. For pre-and immediately after LA treatment, the LDL-C was (5.20±2.94) mmol/L vs. (1.83±1.08) mmol/L, Lp(a) concentration was 428.70(177.00, 829.50)mg/L vs. 148.90(75.90, 317.00) mg/L (P<0.001), with a decrease of 64.2% and 59.8% respectively. The levels of IgG and IgA measured 1 day after LA treatment were both in the normal range and IgM concentration was below the reference value, the reductions of which were 15.1%, 25.0% and 58.7% respectively (P<0.001). Six patients had mild symptoms of nausea, hypotension dyspnea and palpitation, the symptoms were relieved by symptomatic treatment. Conclusion: For patients with FH who do not achieve LDL-C target goal with the maximal tolerated lipid-lowering agents, especially those with elevated Lp(a) levels, LA, which can significantly further reduce LDL-C and Lp(a) levels, is an effective and safe option.

Identificación de variantes genéticas asociadas a hipercolesterolemia familiar en niños y adolescentes de la Región del Biobío, Chile / Identification of genetic variants associated with familial hypercholesterolemia in Chilean children and adolescents

Background: Familial hypercholesterolemia (FH) is commonly associated with mutations in-LDL receptor (LDLR), apolipoprotein B (APOB) and proprotein convertase subtilisin/kexin type 9 (PCSK9). Aim: To identify genetic variants associated with FH in a population of children and adolescents with hypercholesterolemia or a family history of-demonstrated early CVD. Material and Methods: Clinical and biochemical parameters were evaluated, and nine genes related to FH were sequenced namely LDLR, APOB, PCSK9, LDLRAP1, LIPA, APOE, ABCG5, ABCG8 and STAP1, in 55 children and adolescents aged 1 to 18 years old, from non-consanguineous families. Results: Mutations associated with FH were found in 17 children and adolescents, corresponding to p.Asp47Asn, duplication of exons 13-15 and p.Ser326Cys of the LDLR gene; p.Glu204* and Ile268Met of the APOE gene. Thirteen patients were heterozygous, two homozygous, two compound heterozygous, and one double heterozygous. Conclusions: Children and adolescents carrying mutations associated with FH were found by selective screening, which constitutes the first stage in the identification of genetic variants in our country.

Percepção Inadequada do Risco Cardiovascular e Baixo Conhecimento sobre Hipercolesterolemia Familiar em Indivíduos com Hipercolesterolemia Grave / Cardiovascular Risk Misperception and Low Awareness of Familial Hypercholesterolemia in Individuals with Severe Hypercholesterolemia

Resumo Fundamento Indivíduos com hipercolesterolemia grave apresentam alto risco de desenvolver doença cardiovascular aterosclerótica (DCVA). Muitos deles apresentam hipercolesterolemia familiar (HF). Objetivos Avaliar, a partir da perspectiva dos pacientes, o nível de conhecimento sobre a hipercolesterolemia grave, especialmente em relação a HF, DCVA, percepção de risco, desempenho do rastreamento em cascata e tratamento de indivíduos participantes de um programa de avaliação periódica de saúde. Métodos De um banco de dados de 70.000 brasileiros avaliados entre 2006 e 2016, 1.987 (2,8%) atenderam aos critérios de inclusão (idade ≥ 18 anos e LDL-C ≥ 190 mg/dL ou ≥ 160 mg/dL se sem uso de estatinas ou em terapia com estatinas, respectivamente). Desses, 200 foram aleatoriamente convidados a preencher um questionário extenso. A HF foi diagnosticada em caso de suspeita pelo médico responsável. Resultados Embora 97% da amostra (48±9 anos; 16% do sexo feminino; 95% com ensino superior; 88% em prevenção primária; LDL-C 209±47 mg/dL) tenha apresentado hipercolesterolemia grave, apenas 18% e 29,5% se consideravam de alto risco para desenvolver DCVA e relataram saber sua meta recomendada de LDL-C, respectivamente. Em relação à possibilidade de o colesterol alto ser uma doença hereditária, 58% relataram conhecimento sobre o fato; 24,5% (n = 49) já tinham ouvido falar em HF; e apenas 14% (n = 20) foram previamente identificados com suspeita de HF (idade ao diagnóstico de HF: 35±12 anos; 79% e 31% foram diagnosticados com > 30 e > 40 anos, respectivamente). Apenas 2,5% foram submetidos a testes genéticos; 17%, à rastreamento em cascata; e 17% não faziam uso de tratamento farmacológico. Conclusões Identificou-se uma importante lacuna na percepção de risco, no controle do colesterol e em aspectos relacionados à HF em indivíduos com hipercolesterolemia grave. (Arq Bras Cardiol. 2021; [online].ahead print, PP.0-0)

Abstract Background Individuals with severe hypercholesterolemia are at a high risk of developing atherosclerotic cardiovascular disease (ASCVD). Many of them have familial hypercholesterolemia (FH). Objectives To assess from a patient perspective the degree of awareness about severe hypercholesterolemia, especially FH, ASCVD risk perception, cascade screening performance, and treatment of individuals participating in a routine health evaluation program. Methods From a database of 70,000 Brazilian individuals evaluated between 2006 and 2016, 1,987 (2.8%) met the inclusion criteria (age ≥ 18 years and LDL-C ≥ 190 mg/dL or ≥ 160 mg/dL, respectively, if not in use of statins or on statin therapy). Two-hundred individuals were randomly invited to complete an extensive questionnaire. FH was diagnosed if suspected by the attending physician. Results Although 97% of the sample (age 48±9 years; 16% women; 95% college/university education; 88% primary prevention; LDL-C 209±47 mg/dL) had severe hypercholesterolemia, only 18% and 29.5% believed to be at high ASCVD risk and reported knowledge of their recommended LDL-C goal, respectively. Fifty-eight percent reported being informed that high cholesterol could be a family disease, 24.5% (n = 49) had ever heard about FH, and merely 14% (n = 29) had been previously identified as suspected of having FH (age at FH diagnosis 35±12 years; 79% and 31% diagnosed, respectively, > 30 and > 40 years old). Only 2.5% underwent genetic tests, 17% underwent cascade screening, and 17% were not in use of pharmacological treatment. Conclusions An important gap in risk perception, cholesterol management, and aspects related to FH was encountered in individuals with severe hypercholesterolemia. (Arq Bras Cardiol. 2021; [online].ahead print, PP.0-0)

Application of the MCDA method for assessing new technologies for familial hypercholesterolaemia treatment / Aplicação do método MCDA para avaliar novas tecnologias para o tratamento da hipercolesterolemia familiar

Objective: Familial hypercholesterolaemia is a hereditary disease characterized by very high levels of low-density lipoprotein cholesterol and an elevated risk of early-onset cardiovascular disorders. New drugs provide alternatives for the treatment of patients with homozygous familial hypercholesterolaemia. The study aims to explore a practical application of multiple-criteria decision analysis on prioritization of new and emerging technologies for familial hypercholesterolaemia. Methods: The decision model was constructed using the MACBETH method. There were three stages: structuring the problem, measuring the performance of alternatives, and building the model. The weights for alternatives and levels were obtained by indirect comparisons, which evaluated the attractiveness of the performance levels of the criteria using the swing weights technique. Results: The drugs lomitapide, ezetimibe, evolocumab, and mipomersen were selected as alternatives for decision-making. "Cardiovascular Death", "Stroke" and "Acute Myocardial Infarction" had the three most significant weights. The criteria with the lowest weights were "Comfort" and "LDL-C Reduction". The top-ranked technology was evolocumab, with an overall score of 59.87, followed by ezetimibe, with a score of 37.21. Conclusion: How to apply the result of a higher score in the actual decisionmaking process still requires further studies. The case in question showed that evolocumab has more performance benefits than other drugs but with a cost approximately 50 times higher

Objetivo: A hipercolesterolemia familiar é uma doença hereditária caracterizada por níveis muito elevados de lipoproteína de baixa densidade (LDL-colesterol) e um risco elevado de doenças cardiovasculares de início precoce. Novos medicamentos oferecem alternativas para o tratamento de pacientes com hipercolesterolemia familiar homozigótica. Esse estudo tem como objetivo explorar uma aplicação prática da análise de decisão multicritério na priorização de tecnologias novas e emergentes para hipercolesterolemia familiar. Métodos: O modelo de decisão foi construído usando o método MACBETH. Três etapas foram criadas: estruturação do problema, mensuração do desempenho das alternativas e construção do modelo. Os pesos para alternativas e níveis foram obtidos por comparações indiretas, que avaliaram a atratividade dos níveis de desempenho dos critérios usando a técnica de pesos de balanço. Resultados: Os medicamentos lomitapida, ezetimiba, evolocumabe e mipomersen foram selecionados como alternativas para a tomada de decisão. "Morte Cardiovascular", "Acidente vascular cerebral" e "Infarto Agudo do Miocárdio" tiveram os três pesos mais significativos. Os critérios com os menores pesos foram "Conforto" e "Redução do LDL-C". A tecnologia mais bem avaliada foi o evolocumabe, com pontuação geral de 59,87, seguido da ezetimiba, com pontuação de 37,21. Conclusão: Ainda são necessários estudos para determinar como aplicar o resultado de uma pontuação mais alta no processo de tomada de decisão. O caso em questão demonstrou que o evolocumabe tem benefícios mais significativos em relação aos outros medicamentos, mas com um custo cerca de 50 vezes maior

Executive summary of the 2020 Clinical practice guidelines for the management of Dyslipidemia in the Philippines / Journal of the ASEAN Federation of Endocrine Societies

@#Dyslipidemia is a cardiovascular risk factor that is increasing in prevalence in the country. The need to treat and manage elevated cholesterol levels, both pharmacologic and non-pharmacologic, is of utmost importance. Different medical societies and groups bonded together to formulate the 2020 Philippine Clinical Practice Guidelines for dyslipidemia. The group raised nine clinical questions that are important in dyslipidemia management. A technical working group analyzed the clinical questions dealing with non-pharmacologic management, primary prevention for both non-diabetic and individuals with diabetes, familial hypercholesterolemia, secondary prevention, adverse events of statins and the use of other lipid parameters as measurement of risk for cardiovascular disease. Randomized controlled trials and meta-analyses were included in the GRADE-PRO analysis to come up with the statements answering the clinical questions. The statements were presented to a panel consisting of government agencies, members of the different medical societies, and private institutions, and the statements were voted upon to come up with the final statements of the 2020 practice guidelines. The 2020 CPG is aimed for the Filipino physician to confidently care for the individual with dyslipidemia and eventually lower his risk for cardiovascular disease.

The relationship between genotype of familial hypercholesterolemia and the efficacy of PCSK9 inhibitors / 中华心血管病杂志

Objective: This study intends to explore the difference in the efficacy of PCSK9 inhibitors in patients with different FH phenotypes by analyzing the level of blood lipids before and after treatment with PCSK9 inhibitors in patients with familial hypercholesterolemia (FH) with different allele grades. Methods: Patients with FH phenotype, who admitted to Beijing Anzhen Hospital from January 2019 to October 2020, were enrolled. Age, sex and other clinical information were collected from enrolled, and the pathogenic genes were detected by the second generation sequencing technique. The patients were divided into five groups according to the number of alleles involved and the degree of gene damage: single allele-null mutation group, single allele-defect mutation group, multi-allele-null mutation group, multi-allele-defect mutation group and no major pathogenic gene mutation group. The results of blood lipids were collected before medication, 4-6 weeks of intensive statin treatment and one month after combined treatment with PCSK9 inhibitor (PCSK9i). The LDL-C level were compared among groups. ASCVD risk stratification was performed in all patients, and the proportion of LDL-C level reaching the corresponding risk stratification target value of each genotype group after treatment was analyzed. Results: A total of 66 patients with FH phenotype were included, including 47 males (71.2%) and 19 females (28.8%),the mean age was(43.1±13.4 years). There were 7 cases in single allele-null mutation group (10.6%), 25 cases in single allele-defect mutation group (37.9%), 8 cases in multi-allele-null mutation group (12.1%), 18 cases in multi-allele-defect mutation group (27.3%) and 8 cases in no major pathogenic mutation group (12.1%). The degree of LDL-C reduction post combined PCSK9 inhibitor therapy was as follows: single allele mutation group>no major pathogenic mutation group>multi-allele mutation group, general distribution was in the range of 0-90.0%. Two groups of single allele mutation and no major pathogenic mutation group>50.0%>multi-allele mutation group. Under the combined treatment of PCSK9 inhibitors, the further decrease of LDL-C was in the order of single allele mutation group>non-major pathogenic mutant group>multi-allele mutation group. The efficacy of combined therapy on reducing LDL-C at 1 month after treatment decreased with the increase of baseline LDL-C level (r = 0.46, P<0.001) in patients with FH phenotype. In addition, the further decrease of LDL-C level post high-intensity statin therapy combined with PCSK9 inhibitors decreased with the increase of baseline LDL-C levels (r = 0.40, P<0.001). The degree of LDL-C decrease was high and stable by statin combined with PCSK9 inhibitor therapy in single allele mutation group. In the single allele-defect mutant group, the decrease of LDL-C increased with the increase of baseline LDL-C level post intensive statin treatment and combined PCSK9 inhibitor treatment ((r=0.54, P=0.009); r=0.45,P=0.030), and the further decrease of LDL-C level decreased with the increase of baseline LDL-C level in single allele-defect mutant group post combined therapy with PCSK9 inhibitor (r=0.43, P=0.040). The decrease of LDL-C in patients with the multi-allele mutation group varied with different pathogenic gene loci and combinations post combined therapy with PCSK9 inhibitor. There was no significant difference in the level of blood lipids between the group without major pathogenic gene mutation and the group with single allele mutation before and after treatment. The percentage of patients achieving LDL-C goals with different genotypes of phenotypic FH were as follows: single allele mutation group (86.7%), non-major pathogenic mutant group (75.0%) and multi-allele mutation grou (<5.0%). Conclusions: All patients with different FH phenotypes could benefit from the intensive lipid-lowering therapy with statins and PCSK9 inhibitors, however, there are significant differences in the efficacy of lowering LDL-C in Chinese patients with FH phenotype with different molecular etiologies. Therefore, the pathogenic gene analysis may suggest the lipid-lowering effect of PCSK9 inhibitors in patients with FH.

Cross sectional study of familial hypercholesterolemia in dyslipidemia patients receiving lipid-lowering therapy: DYSIS-China subgroup analysis / 中华心血管病杂志

Objectives: To analyze the incidence, blood lipid levels and cardiovascular disease of familial hypercholesterolemia (FH) in dyslipidemia patients receiving lipid-lowing therapy from the DYSIS-China. Methods: Dyslipidemia International Study-China (DYSIS-China) database was re-analyzed according to the criteria of "Chinese guidelines for prevention and treatment of dyslipidemia in adults-2016 version". DYSIS-China database included 25 317 dyslipidemia out-patients who received at least one lipid-lowering drug for at least three months. All the patients were divided into three groups: unlikely HF, possible FH and definite FH according to the Dutch Lipid Clinic Network diagnostic criteria. Age, gender, lipids levels, drug use and complications were compared among the three groups. Factors were compared between Possible FH group and definite FH group in terms of age stratification. Results: A total of 23 973 patients with dyslipidemia were included. The average age was (64.8±9.9) years, 11 757 patients were females (49.0%). The proportion of unlikely FH in the total population was 20 561 (85.7%), possible FH was 3294 (13.7%), and the definite FH was 118(0.5%). Patients in the definite FH group (58.3±8.5 years) was younger than in unlikely HF(65.3±9.8 years) and possible FH(61.8±9.9 years) group. LDL-C ((5.6±1.9) mmol/L) levels were significantly higher in definite FH group than in unlikely HF ((2.5±0.9) mmol/L) and possible FH ((4.3±1.0) mmol/L) group. TC ((7.4±1.8) mmol/L) levels were also significantly higher in definite FH group than in unlikely HF ((4.3±1.0) mmol/L) and possible FH ((6.0±1.0) mmol/L) group. Percent of female sex, sedentary lifestyle and systolic blood pressure value were significantly higher in definite FH group than in other two groups (all P<0.05). Statin use was similar among the 3 groups. Prevalence of ischemic cardiomyopathy (70(59.3%)) was significantly higher in the definite FH group than in unlikely FH group7519 (36.6%) and possible FH group1149 (34.9%). The rate of hypertension (82 (69.5%)) was also significantly higher in the definite FH group than in unlikely FH group (2 063 (62.6%) and in possible FH group (13 928 (67.7%)). The possible FH group had the highest proportion of patients aged 55-64 years (1 146 (34.8%)), and the prevalence of hypertension 358 (76.8%), diabetes 189 (40.6%), ischemic heart disease 186 (39.9%), cerebrovascular disease 149 (32.0%) and heart failure 28 (6.0%) was the highest in patients over 75 years old. The definite FH group had the highest proportion of patients aged 55-64 years (49 (41.52%)), and the prevalence of ischemic heart disease (70 (59.3%)) was the highest in patients aged 45-54 years old group, there was no significant difference in the prevalence of diabetes,hypertension,heart failure,peripheral artery disease and cerebrovascular disease among different age groups. Conclusion: The detection rate of FH in Chinese patients with dyslipidemia is not low, the blood lipid level is poorly controlled, and the risk of cardiovascular disease is high in Chinses FH patients.

Hipercolesterolemia familiar: serie de 36 casos con fenotipo de hipercolesterolemia familiar homocigótica / Familial hypercholesterolaemia: A study of 36 cases with a phenotype of homozygous familiar hypercholesterolaemia

Resumen Introducción: La hipercolesterolemia familiar homocigótica (HFHo) se caracteriza por niveles muy elevados de cLDL y por enfermedad aterosclerótica temprana. Aunque la frecuencia es baja (1/300.000), las complicaciones son muy severas y pueden ser evitadas. Encontrar y tratar esta población de manera temprana podría reducir la mortalidad. Se describen 36 casos en Colombia, en donde se calcula que haya entre 160 y 200 casos. Resultados: Un total de 36 pacientes con fenotipo sugestivo de HFHo fueron identificados y tratados en un período de observación de cuatro años. La media de edad fue 27 años (24 mujeres). 34 pacientes tuvieron un puntaje según la Red de Clínicas de Lípidos de Holanda (RCLH) mayor de 8 (diagnóstico definitivo) y los restantes 2 tenían puntaje equivalente a diagnóstico probable. Un cuarto de los casos procedían de la costa norte colombiana. En las pruebas genéticas, 14 fueron homocigóticos verdaderos para mutación del gen que codifica para el receptor de LDL (LDLR), 12 heterocigóticos compuestos, 2 heterocigóticos dobles y uno autosómico recesivo (LDLRAP1); 5 pacientes fueron heterocigóticos simples (LDLR) y 2 pacientes no autorizaron la prueba. En los homocigóticos verdaderos, la variante más frecuente encontrada fue la c.11G>A. 14 pacientes cursaron con enfermedad coronaria, 9 con estenosis carotídea, 8 con estenosis aórtica y 2 tuvieron ataques cerebrovasculares (ACV). 34 pacientes recibían estatinas (24 rosuvastatina), 30 recibían ezetimibe, 2 recibían evolocumab y 20 recibían lomitapide (dosis promedio 12,7mg). Ninguno recibió aféresis de cLDL. Los medicamentos, en general, fueron bien tolerados y la reducción promedio de cLDL con la terapia fue de 533,7mg/dl a 245,1mg/dl (54%). Conclusiones: Todos los pacientes recibieron tratamiento hipolipemiante y se encontraron alteraciones genéticas diagnósticas en todos aquellos que autorizaron el examen. Los niveles elevados de cLDL conllevan tanto riesgo que el tratamiento debe establecerse aún sin conocer el diagnóstico genético.

Abstract Background: Homozygous familial hypercholesterolemia (HoFH) is characterized for very high levels of cLDL and early cardiovascular disease. Although incidence is low (1/300 000), complications are very severe and can be avoided. Finding and treating this population promptly could reduce mortality. We describe 36 cases in Colombia, where 160 to 200 cases are expected. Results: 36 patients with phenotype of HoHF were identified and treated in a follow-up of 4 years. The mean age was 27 years (24 women). 34 of them had at least 8 points in the FH Dutch Lipid Clinic Criteria (definitive diagnosis) and two had probable diagnosis. A quarter of the cases came from the Colombian North Coast. In molecular tests, 14 were true homozygous for LDLR, 12 were compound heterozygous for LDLR, 2 double heterozygous and one was autosomal recessive; 5 were heterozygous and 2 patients did not authorized genetic test. In true homozygous subjects, the most frequent variant was c.11G>A. 14 patients had coronary disease, 9 carotid stenosis, 8 aortic stenosis and 2 had stroke. 34 patients were on statins (25 rosuvastatin), 30 were receiving ezetimibe, 2 were receiving a PSCK9 inhibitor (evolocumab) and 20 were on lomitapide with mean doses of 12.7mg. None received lipoprotein apheresis. Medications were very well tolerated. Changes in cLDL after therapy was from 533.7 mg/dL to 245 mg/dL, (54%). Conclusions: Treatment was started in all patients. We found genetic mutations in all patients with genetic tests. The high levels of cLDL mean such a high risk that treatment must be started promptly, even without a genetic test.

Portador Heterozigoto Composto de Hipercolesterolemia Familiar Causada por Variantes no LDLR / Compound Heterozygous Familial Hypercholesterolemia Caused by LDLR Variants

Resumo A hipercolesterolemia familiar (HF) é uma doença genética causada por um defeito primário no gene que codifica o receptor da LDL. Mutações diferentes no mesmo gene caracterizam um heterozigoto composto, mas pouco se sabe sobre o fenótipo dos portadores. Portanto, neste estudo, descrevemos o rastreamento em cascata de uma família brasileira com essa característica. O caso-índice é um homem de 36 anos, com colesterol total (CT) de 360 mg/dL (9,3 mmol/L) e concentração de LDL-c de 259 mg/dL (6,7 mmol/L), além de xantomas de tendão de Aquiles, obesidade e pré-hipertensão. A genotipagem identificou as mutações 661G>A, 670G>A e 682G>A, no exon 4, e 919G>A, no exon 6. A mesma mutação no exon 4 foi observada no filho do caso-índice (7 anos), que também tem hipercolesterolemia e xantomas tendinosos, ao passo que a filha do caso-índice (9 anos) apresenta mutação no exon 6 e hiperlipidemia, sem xantomas. Em suma, este relato permite uma melhor compreensão acerca da base molecular da HF no Brasil, um país multirracial, onde é esperada uma população heterogênea.

Abstract Familial hypercholesterolemia (FH) is a genetic disease caused by a primary defect in the LDL-receptor gene. Distinct variants in the same gene characterize a compound heterozygote, but little is known about the phenotypes of the carriers. Therefore, herein, we describe the cascade screening of a Brazilian family with this characteristic. The index case, a 36-year-old male, had a total cholesterol level of 360 mg/dL (9.3 mmol/L) and LDL-c value of 259 mg/dL (6.7 mmol/L), in addition to Achilles tendon xanthomas, obesity and prehypertension. Genotyping identified the variants 661G>A, 670G>A, 682G>A in exon 4 and 919G>A in exon 6. The same variant in exon 4 was found in the index case's son (7-y), who also had hypercholesterolemia and xanthomas, while the index case's daughter (9-y) had the variant in exon 6 and hyperlipidemia, without xanthomas. In summary, this report allows for a better insight into the molecular basis of FH in Brazil, a multi-racial country where a heterogeneous population is expected.

Association between magnesium, selenium and zinc consumption and lipid profile of brazilian adolescents / Asociación entre el consumo de magnesio, selenio y zinc y el perfil lipídico de los adolescentes brasileños

ABSTRACT The study aims to evaluate the association between inadequate consumption of antioxidant minerals and plasma lipoprotein concentrations in adolescents. We conducted a cross-sectional study that evaluated sociodemographic and anthropometric data, information on intake of magnesium, selenium and zinc and lipid profile. Student's t-test was used to compare means between the groups and logistic regression to verify the strength of the association between the independent variables and lipid profile. Inadequate zinc consumption was associated with a higher chance of low HDL-c levels and lower chance of hypertriglyceridemia and high LDL-c levels. Inadequate selenium intake was associated with a lower chance of high total cholesterol and of high triglyceride concentrations and a higher chance of low HDL-c levels. Inadequate magnesium consumption was associated with a higher chance of high cholesterol and triglyceride levels, a lower chance of high LDL-c levels and with a higher chance of low HDL-c. We observed an association between inadequate consumption of magnesium, zinc and selenium and changes in the lipid profile of adolescents.

RESUMEN El estudio tiene como objetivo evaluar la asociación entre el consumo inadecuado de minerales antioxidantes y las concentraciones plasmáticas de lipoproteínas en adolescentes. Estudio transversal que evaluó datos sociodemográficos y antropométricos, información sobre ingesta de magnesiom selenio y zinc y perfil lipídico. Se utilizó la prueba t de Student para comparar medias entre los grupos y regresión logística para verificar la fuerza de la asociación entre las variables independientes y el perfil lipídico. El consumo inadecuado de zinc se asoció con una mayor probabilidad de niveles bajos de HDL-c y una menor probabilidad de hipertrigliceridemia y niveles altos de LDL-c. La ingesta inadecuada de selenio se asoció con una menor probabilidad de colesterol total alto y de altas concentraciones de triglicéridos y una mayor probabilidad de niveles bajos de HDL-c. El consumo inadecuado de magnesio se asoció con una mayor probabilidad de niveles altos de colesterol y triglicéridos, una menor probabilidad de niveles altos de LDL-c y una mayor probabilidad de niveles bajos de HDL-c. El estudio muestra una asociación entre el consumo inadecuado de magnesio, zinc y selenio y los cambios en el perfil lipídico de los adolescentes.

Phenotype of definite familial hypercholesterolemia with negative genetic study in Argentina / Fenotipo de hipercolesterolemia familiar definitivo con estudio genético negativo en Argentina

Abstract Objective: Familial hypercholesterolemia (FH) is a monogenic disease, associated with variants in the LDLR, APOB and PCSK9 genes. The initial diagnosis is based on clinical criteria like the DLCN criteria. A score > 8 points qualifies the patient as "definite" for FH diagnosis. The detection of the presence of a variant in these genes allows carrying out familial cascade screening and better characterizes the patient in terms of prognosis and treatment. Methods: In the context of the FH detection program in Argentina (Da Vinci Study) 246 hypercholesterolemic patients were evaluated, 21 with DLCN score > 8 (definite diagnosis).These patients were studied with next generation sequencing to detect genetic variants, with an extended panel of 23 genes; also they were adding the large rearrangements analysis and a polygenic score of 10 SNP (single nucleotide polymorphism) related to the increase in LDL-c. Results: Of the 21 patients, 10 had variants in LDLR, 1 in APOB with APOE, 1 in LIPC plus elevated polygenic score, and 2 patients showed one deletion and one duplication in LDLR, the later with a variation in LIPA. It is highlighted that 6 of the 21 patients with a score > 8 did not show any genetic alteration. Conclusions: We can conclude that 28% of the patients with definite clinical diagnosis of FH did not show genetic alteration. The possible explanations for this result would be the presence of mutations in new genes, confusing effects of the environment over the genes, the gene-gene interactions, and finally the impossibility of detecting variants with the current available methods.

Resumen Objetivo: La hipercolesterolemia familiar (HF) es una enfermedad monogénica asociada a variantes en los genes RLDL, APOB y PCSK9. El diagnóstico inicial se basa en criterios clínicos, como el de la red de clínica de lípidos holandesa (DLCN). Un puntaje > 8 puntos califica al paciente como "definitivo" para diagnóstico de HF. La identificación de una variante en estos genes permite realizar el cribado en cascada familiar y caracterizar mejor al paciente en cuanto al pronóstico y el tratamiento. Métodos: En el marco del Programa de Detección de HF en Argentina (Estudio Da Vinci) se evaluó a 246 pacientes hipercolesterolémicos, 21 con puntaje DLCN > 8 (diagnóstico definitivo). Se estudió a estos pacientes con secuenciación de próxima generación para reconocer variantes genéticas, con un panel ampliado de 23 genes, sumado al análisis de grandes rearreglos y por último se aplicó un score poligénico de 10 SNP (polimorfismo de nucleótido único) relacionados con aumento del c-LDL. Resultados: De los 21 pacientes, 10 presentaron variantes en RLDL, uno en APOB junto a APOE, uno en LIPC más puntaje poligénico elevado, dos pacientes con una deleción y una duplicación en RLDL y este último caso con una variante en LIPA. Es destacable que 6 de los 21 pacientes con puntaje DLCN > 8 no mostraron ninguna alteración genética. Conclusiones: El 28% de los pacientes con diagnóstico clínico definitivo de HF no evidenció alteración genética. Las posibles explicaciones de este resultado serían la presencia de mutaciones en nuevos genes, los efectos confundidores del ambiente sobre los genes o la interacción gen-gen y por último la imposibilidad de detectar variantes con la metodología actual disponible.