Clinical and genetic analysis of five Chinese pedigrees affected with short stature due to variants of ACAN gene / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical and genetic characteristics of five Chinese pedigrees affected with short stature.@*METHODS@#A retrospective analysis was carried out for the clinical data and results of genetic testing for the probands. A literature search was also conducted.@*RESULTS@#The five probands have all featured short stature with a family history. Genetic testing has revealed that they have harbored variants of the ACAN gene, including p.Val2042Argfs*6, p.Val1597del, c.630-1G>A, c.23delT and c.2026+1G>A(previously reported).@*CONCLUSION@#Except for short stature, children harboring heterozygous variants of the ACAN gene may have no involvement of other systems. Some of these children may response to short-term growth hormone treatment.

Genetic causes of isolated short stature

ABSTRACT Short stature is a common feature, and frequently remains without a specific diagnosis after conventional clinical and laboratorial evaluation. Longitudinal growth is mainly determined by genetic factors, and hundreds of common variants have been associated to height variability among healthy individuals. Although isolated short stature may be caused by the combination of variants, with a deleterious impact on the growth of individuals with polygenic inheritance, recent studies have pointed out some monogenic defects as the cause of the growth disorder observed in nonsyndromic children. The majority of these defects are in genes related to the growth plate cartilage and in the growth hormone (GH) - insulin-like growth factor 1 (IGF-1) axis. Affected patients usually present the mildest spectrum of some forms of skeletal dysplasia, or subtle abnormalities of laboratory tests, suggesting hormonal resistance or insensibility. The lack of specific characteristics, however, does not allow formulation of a definitive diagnosis without the use of broad genetic studies. Thus, molecular genetic studies including panels of genes or exome analysis will become essential in investigating and identifying the causes of isolated short stature in children, with a crucial impact on treatment and follow-up.

Síndrome H: primer caso pediátrico reportado en América Latina / H syndrome: First reported paediatric case in Latin America

Introducción: El síndrome H es una enfermedad genética extremadamente rara de compromiso multisistémico, el cual clínicamente puede ser reconocido de forma precoz, ofreciendo de manera oportuna un seguimiento, tratamiento específico y asesoramiento genético. Objetivo: Presentar un caso con características «típicas del síndrome H¼ para favorecer su identificación precoz. Caso clínico: Varón de 8 años de edad, evaluado por tumoraciones testiculares, lesiones dérmicas tipo hiperpigmentación con hipertricosis, retraso del lenguaje, talla baja, deformidades articulares, hipoacusia neurosensorial bilateral, anemia, hipergammaglobulinemia y alteraciones óseas. En los estudios histológicos de la piel y las masas testiculares se observó infiltración linfoplasmocitaria. El secuenciamiento del gen SLC29A3 detectó una mutación homocigota c.1087 C>T (p.Arg363Trp; rs387907067) concluyente con el síndrome H, la cual ha sido reportada previamente. Conclusiones: Este es el primer caso reportado en Latinoamérica del síndrome H, cuyas características descritas son parte del espectro clínico. El hallazgo clínico principal, que orienta al diagnóstico, es la hiperpigmentación acompañada de hipertricosis.

Introduction: H Syndrome is an extremely rare genetic disease, with a multisystemic character and which can be identified in early childhood, offering the opportunity of specific treatment and genetic counselling. Objective: To present a clinical case with "typical" characteristics of H Syndrome. Clinical case: The case is presented of an 8-year-old male patient who presented with testicular tumours and skin lesions characterised by hyperpigmentation with hypertrichosis, language delay, short stature, and joint deformities. He also presented with bilateral sensorineural hearing loss, anaemia, hypergammaglobulinaemia, and bone disorders. Histopathology studies of the skin and testicular masses reported lymphoplasmacytic infiltration. Sequencing analysis of gene SLC29A3 showed the homozygote mutation c.1087 C>T (p.Arg363Trp; rs387907067). Conclusions: These findings are consistent with H syndrome, and this is the first reported case in Latin America. The key to the diagnosis is the finding of hyperpigmentation with hypertrichosis.

Benefits of maltodextrin intake 2 hours before cholecystectomy by laparotomy in respiratory function and functional capacity: a prospective randomized clinical trial / Benefícios na função respiratória e capacidade funcional com ingesta de maltodextrina 2 horas antes de colecistectomia por laparotomia: ensaio clínico prospectivo e randomizado

ABSTRACT Objective: To evaluate the change in respiratory function and functional capacity according to the type of preoperative fasting. Methods: Randomized prospective clinical trial, with 92 female patients undergoing cholecystectomy by laparotomy with conventional or 2 hours shortened fasting. The variables measured were the peak expiratory flow, forced expiratory volume in the first second, forced vital capacity, dominant handgrip strength, and non-dominant handgrip strength. Evaluations were performed 2 hours before induction of anesthesia and 24 hours after the operation. Results: The two groups were similar in preoperative evaluations regarding demographic and clinical characteristics, as well as for all variables. However, postoperatively the group with shortened fasting had higher values than the group with conventional fasting for lung function tests peak expiratory flow (128.7±62.5 versus 115.7±59.9; p=0.040), forced expiratory volume in the first second (1.5±0.6 versus 1.2±0.5; p=0.040), forced vital capacity (2.3±1.1 versus 1.8±0.9; p=0.021), and for muscle function tests dominant handgrip strength (24.9±6.8 versus 18.4±7.7; p=0.001) and non-dominant handgrip strength (22.9±6.3 versus 17.0±7.8; p=0.0002). In the intragroup evaluation, there was a decrease in preoperative compared with postoperative values, except for dominant handgrip strength (25.2±6.7 versus 24.9±6.8; p=0.692), in the shortened fasting group. Conclusion: Abbreviation of preoperative fasting time with ingestion of maltodextrin solution is beneficial to pulmonary function and preserves dominant handgrip strength. .

RESUMO Objetivo: Avaliar a alteração da função respiratória e da capacidade funcional, conforme o tipo de jejum pré-operatório. Métodos: Ensaio clínico prospectivo randomizado, com 92 pacientes do sexo feminino, submetidas à colecistectomia por laparotomia, observando jejum convencional ou abreviado de 2 horas com maltodextrina. As variáveis foram: pico de fluxo expiratório, volume expiratório no primeiro segundo, capacidade vital forçada, força de preensão palmar dominante e força de preensão palmar não dominante. As avaliações foram realizadas 2 horas antes da indução anestésica e 24 horas após a operação. Resultados: Os dois grupos foram semelhantes quanto às características demográficas, clínicas e em todas as variáveis estudadas, quando avaliadas no pré-operatório. No entanto, no pós-operatório, o grupo abreviado apresentou valores maiores que o grupo convencional para pico de fluxo expiratório (128,7±62,5 versus 115,7±59,9; p=0,040), volume expiratório no primeiro segundo (1,5±0,6 versus 1,2±0,5; p=0,040), capacidade vital forçada (2,3±1,1 versus 1,8±0,9; p=0,021), força de preensão palmar dominante (24,9±6,8 versus 18,4±7,7; p=0,001) e força de preensão palmar não dominante (22,9±6,3 versus 17,0±7,8; p=0,0002). Na avaliação intragrupo, houve diminuição nas variáveis ao se compararem os valores do pré-operatório em relação ao pós-operatório, exceto para força de preensão palmar dominante (25,2±6,7 versus 24,9±6,8; p=0,692) no grupo de jejum abreviado. Conclusão: A abreviação do tempo de jejum pré-operatório com solução contendo maltodextrina beneficia a função pulmonar e preserva a força de preensão palmar dominante. .

Reabilitação da deglutição em pacientes traqueostomizados disfágicos sob ventilação mecânica em unidades de terapia intensiva: um estudo de factibilidade / Swallowing rehabilitation of dysphagic tracheostomized patients under mechanical ventilation in intensive care units: a feasibility study

Objetivo: Avaliar a factibilidade da implantação precoce de um programa de reabilitação da deglutição em pacientes traqueostomizados com disfagia e sob ventilação mecânica. Métodos: Estudo prospectivo realizado em unidades de terapia intensiva de um hospital universitário. Incluímos pacientes hemodinamicamente estáveis e submetidos à ventilação mecânica por pelo menos 48 horas e há no mínimo 48 horas com traqueostomia e nível adequado de consciência. Os critérios de exclusão foram cirurgia prévia na cavidade oral, faringe, laringe e/ou esôfago, presença de doenças degenerativas ou história pregressa de disfagia orofaríngea. Todos os pacientes foram submetidos a um programa de reabilitação da deglutição. Antes e após o tratamento de reabilitação da deglutição, foram determinados um escore estrutural orofaríngeo, um escore funcional de deglutição, e um escore otorrinolaringológico estrutural e funcional. Resultados: Foram incluídos 14 pacientes. A duração média do programa de reabilitação foi de 12,4 ± 9,4 dias, com média de 5,0 ± 5,2 dias sob ventilação mecânica. Onze pacientes puderam receber alimentação por via oral enquanto ainda permaneciam na unidade de terapia intensiva após 4 (2 - 13) dias de tratamento. Todos os escores apresentaram melhora significante após o tratamento. Conclusão: Neste pequeno grupo de pacientes, a implantação de um programa precoce de reabilitação da deglutição foi factível, mesmo em pacientes sob ventilação mecânica. .

Objective: The aim of the present study was to assess the feasibility of the early implementation of a swallowing rehabilitation program in tracheostomized patients under mechanical ventilation with dysphagia. Methods: This prospective study was conducted in the intensive care units of a university hospital. We included hemodynamically stable patients under mechanical ventilation for at least 48 hours following 48 hours of tracheostomy and with an appropriate level of consciousness. The exclusion criteria were previous surgery in the oral cavity, pharynx, larynx and/or esophagus, the presence of degenerative diseases or a past history of oropharyngeal dysphagia. All patients were submitted to a swallowing rehabilitation program. An oropharyngeal structural score, a swallowing functional score and an otorhinolaryngological structural and functional score were determined before and after swallowing therapy. Results: We included 14 patients. The mean duration of the rehabilitation program was 12.4 ± 9.4 days, with 5.0 ± 5.2 days under mechanical ventilation. Eleven patients could receive oral feeding while still in the intensive care unit after 4 (2 - 13) days of therapy. All scores significantly improved after therapy. Conclusion: In this small group of patients, we demonstrated that the early implementation of a swallowing rehabilitation program is feasible even in patients under mechanical ventilation. .

Estudo da mutação da STAT5B em Criciúma-Santa Catarina: frequência e caracterização fenotípica de indivíduos heterozigotos / Study of STAT5B mutation in Criciúma - Santa Catarina: frequency and phenotypic characterization of heterozygous individuals

Mutações inativadoras em homozigose no gene do transdutor de sinal e ativador de transcrição 5B (STAT5B) causam insensibilidade ao hormônio de crescimento associada a disfunção imunológica grave que se manifesta na forma de infecções exacerbadas e de repetição, pneumonia intersticial linfocítica e outros eventos autoimunes. A caracterização do fenótipo destas mutações em heterozigose não foi realizada previamente. Dois pacientes descritos com mutação em homozigose na STAT5B (c.424_427del / p.L142RfsX19) são irmãos brasileiros naturais de Criciúma - Santa Catarina, sem consanguinidade conhecida na família. Houve também o relato de dois outros casos semelhantes na cidade, já falecidos, sugerindo que mutações na STAT5B pudessem ser relativamente frequentes nesta região. Os objetivos deste estudo foram investigar a frequência da mutação c.424_427del da STAT5B na população de Criciúma, avaliar a existência de efeito fundador e caracterizar o efeito da mutação c.424_427del da STAT5B em heterozigose sobre o fenótipo antropométrico e hormonal. Para investigar a frequência desta mutação em Criciúma, 1192 indivíduos da população foram genotipados. Foram identificados sete indivíduos heterozigotos, caracterizando uma frequência alélica mínima de 0,29% (intervalo de confiança 95%: 0,08 a 0,5%), significativamente mais alta que a frequência de outras variantes patogênicas da STAT5B descritas em bases de dados públicas. Utilizando-se o equilíbrio de Hardy-Weinberg, foi possível estimar a incidência de casos de homozigotos para o alelo mutado em um a cada 40 anos. No entanto, utilizando-se a maior frequência possível de acordo com o intervalo de confiança, esta incidência poderia atingir um a cada 13 anos. Além disso, foram estudados os pais dos dois casos relatados como semelhantes aos pacientes homozigotos para mutações na STAT5B e estes pais eram portadores da mutação c.424_427del da STAT5B em heterozigose. Para avaliar o efeito fundador, foram analisados dois...

Homozygous inactivating mutations in signal transducer and activator of transcription 5B gene (STAT5B) cause growth hormone insensitivity associated with signs of severe immune dysfunction, such as recurrent infections, lymphoid interstitial pneumonia and other autoimmune events. The phenotypic characterization of these mutations in heterozygous state has not been accomplished previously. Two patients with a homozygous STAT5B mutation (c.424_427del / p.L142RfsX19) are Brazilian brothers born in the city of Criciúma, Santa Catarina, and there is not known consanguinity in their family. Moreover, there was a report about two similar cases in this city, already deceased, suggesting that STAT5B mutations could be relatively frequent in this region. The objectives of this study were to evaluate the frequency of STAT5B c.424_427del mutation in Criciúma, to assess the existence of the founder effect and to characterize the effect of heterozygous STAT5B c.424_427del mutation on anthropometric and hormonal phenotypes. To evaluate the frequency of this mutation in Criciúma, 1192 individuals from the population were genotyped. Seven heterozygous individuals were identified, which characterized a minimum allele frequency of 0.29% (95% confidence interval: 0.08 to 0.5%), significantly higher than the frequency of other pathogenic variants described in public databases. By using the Hardy-Weinberg law, it was possible to estimate the incidence of cases of individuals homozygous for this mutation at one every 40 years. However, by using the highest possible frequency according to the confidence interval, this incidence could reach one every 13 years. Additionally, the parents of the two reported cases who were similar to patients with homozygous STAT5B mutations were genotyped and these parents were heterozygous for STAT5B c.424_427del mutation. To assess the founder effect, two markers near the mutation were analyzed in the two boys homozygous...

Mutações em heterozigose no gene do receptor tipo B dos peptídeos natriuréticos (NPR2) são causa de baixa estatura inicialmente classificada como idiopática / Heterozygous mutations in natriuretic peptide receptor-B gene (NPR2) are cause of short stature initially classified as idiopathic

Nos últimos anos, o sistema do peptídeo natriurético do tipo C (CNP) e seu receptor (NPR-B) foi apontado como um importante regulador do processo de ossificação endocondral. Vários estudos em animais evidenciam o seu papel de estímulo à proliferação e diferenciação de condrócitos e secreção de matriz extracelular. Mutações bialélicas com perda de função do gene do NPR-B (NPR2) levam a uma doença denominada displasia acromesomélica do tipo Maroteaux (AMDM), uma displasia esquelética caracterizada por baixa estatura extrema. Observa-se que familiares de pacientes com AMDM carreadores de mutação no NPR2 têm estatura abaixo da média da população a qual pertencem, sugerindo um papel de mutações em heterozigose do NPR2 como causadoras de baixa estatura idiopática (BEI). Os objetivos deste estudo foram avaliar a presença de mutações no gene NPR2 em um grupo de pacientes com BEI e correlacionar os achados moleculares com o fenótipo dos pacientes e familiares. A região codificadora do gene NPR2 foi sequenciada pelo método de Sanger em 60 pacientes com diagnóstico de BEI. Foram identificadas cinco diferentes variantes alélicas missense em heterozigose no NPR2, cada uma em um único paciente. Essas variantes foram submetidas à análise funcional in vitro para avaliação da atividade da guanililciclase e microscopia confocal para localização intracelular dos receptores NPR-B. As variantes c.226T > C / p.Ser76Pro, c.788G > C / p.Arg263Pro e c.2455C > T / p.Arg819Cys segregam com o fenótipo de baixa estatura dentro das famílias e determinam um prejuízo funcional ao NPR-B. As três variantes geram proteínas que exercem efeito dominante negativo e os receptores NPR-B com as mutações p.Ser76Pro e p.Arg263Pro não se localizam na membrana celular. As variantes c.491C > G / p.Ala164Gly e c.1636A > T / p.Asn546Tyr não segregam com o fenótipo de baixa estatura nas famílias e não se evidenciou um efeito dominante negativo. O escore-Z da altura dos indivíduos carreadores das variantes...

Over the past several years, C-type natriuretic peptide (CNP) and its receptor (NPR-B) system has emerged as an important regulator of endochondral bone growth. Animal models showed a CNP/NPR-B role in promoting chondrocyte proliferation and differentiation and matrix synthesis. Biallelic loss-of-function mutations in NPR-B gene (NPR2) cause acromesomelic dysplasia type Maroteux (AMDM), a skeletal dysplasia with extreme short stature. Relatives of patients with AMDM, heterozygous for NPR2 mutations, were noted to be shorter than expected for their population of origin, suggesting that heterozygous mutations in NPR2 could be a cause of idiopathic short stature (ISS). The objective of this study was to investigate the presence of NPR2 mutations in a group of patients with ISS and to correlate molecular findings with phenotype. The NPR2 coding region was sequenced by Sanger's method in 60 patients with ISS. Five different heterozygous missense variants in NPR2 were identified in five patients. The functional consequences of those variants were established using in vitro cell-based assay to determine guanylate cyclase activity and confocal microscopy to determine intracellular localization of NPR-B. The variants c.226T > C / p.Ser76Pro, c.788G > C / p.Arg263Pro and c.2455C > T / p.Arg819Cys segregated with short stature phenotype and were functionally deleterious. NPR-B receptors with these three variants have a dominantnegative effect and p.Ser76Pro and p.Arg263Pro NPR-B were not localized in the cell membrane. Cosegregation analysis of the variants c.491C > G / p.Ala164Gly and c.1636A > T / p.Asn546Tyr was inconclusive and they did not have a dominant negative effect. Carriers of functionally deleterious variants have a height SD score that ranged from -4.5 to -1.7. One of these patients and two relatives have disproportionate short stature and one has shortened metacarpal. In conclusion, heterozygous mutations in NPR2 gene are cause of short stature in...

45,X/46,XY mosaicism: report on 14 patients from a Brazilian hospital. A retrospective study / Mosaicismo 45,X/46,XY: relato de 14 pacientes de um hospital do Brasil. Um estudo retrospectivo

CONTEXT AND OBJECTIVE: 45,X/46,XY mosaicism, or mixed gonadal dysgenesis, is considered to be a rare disorder of sex development. The aim of our study was to investigate the clinical and cytogenetic characteristics of patients with this mosaicism. DESIGN AND SETTING: A retrospective study in a referral hospital in southern Brazil. METHODS: Our sample consisted of patients diagnosed at the clinical genetics service of a referral hospital in southern Brazil, from 1975 to 2012. Clinical and cytogenetic data were collected from the medical records. RESULTS: Fourteen patients were included in the sample, with ages at the first evaluation ranging from 2 days to 38 years. Nine of them had female sex of rearing and five, male. Regarding the external genitalia, most were ambiguous (n = 10). One patient presented male phenotype and was treated for a history of azoospermia, while three patients presented female phenotype, of whom two had findings of Turner syndrome and one presented secondary amenorrhea alone. Some findings of Turner syndrome were observed even among patients with ambiguous genitalia. None presented gonadal malignancy. One patient underwent surgical correction for genital ambiguity and subsequent exchange of sex of rearing. Regarding cytogenetics, we did not observe any direct correlation between percentages of cell lines and phenotype. CONCLUSIONS: 45,X/46,XY mosaicism can present with a wide variety of phenotypes resulting from the involvement of different aspects of the individual. All these observations have important implications for early recognition of these patients and their appropriate management. .

CONTEXTO E OBJETIVO: O mosaicismo 45,X/46,XY, ou disgenesia gonadal mista, é considerado uma doença rara do desenvolvimento sexual. O objetivo do nosso estudo foi verificar as características clínicas e citogenéticas de pacientes com este mosaicismo. TIPO DE ESTUDO E LOCAL: Estudo retrospectivo em um hospital de referência no sul do Brasil. MÉTODOS: Nossa amostra foi composta por pacientes diagnosticados em um serviço de genética clínica de um hospital de referência no sul do Brasil, no período de 1975 até 2012. Os dados clínicos e citogenéticos foram coletados a partir dos prontuários médicos. RESULTADOS: Catorze pacientes foram incluídos na amostra, idades na primeira avaliação variando de 2 dias a 38 anos. Nove deles apresentavam sexo feminino de criação e cinco, masculino. A genitália externa, na maioria, era ambígua (n = 10). O paciente com fenótipo masculino foi tratado por história de azoospermia, enquanto que das três pacientes do fenótipo feminino, duas apresentavam achados da síndrome de Turner e a outra, amenorreia secundária isolada. Alguns achados da síndrome de Turner foram observados mesmo entre pacientes com genitália ambígua. Nenhum deles apresentou neoplasia gonadal. Um paciente foi submetido à correção cirúrgica de ambiguidade genital e posterior troca de sexo de criação. Quanto à citogenética, não observamos correlação direta entre a porcentagem de linhas de células e o fenótipo. CONCLUSÕES: O mosaicismo 45,X/46,XY pode apresentar grande variedade de fenótipos resultantes do envolvimento de diferentes aspectos do indivíduo. Todas essas observações têm implicações importantes para o reconhecimento precoce desses pacientes e seu adequado manejo. .

Variables perinatales de recién nacidos de madres Aymara sugieren adaptación genética a la altura / Perinatal variables from newborns of Aymara mothers suggest a genetic adaptation to high altitude

Background: Studies performed in Andean populations living in high altitude, indicate that the reduced availability of oxygen could be associated to both a fetal growth retardation and a lower birth weight. These variables are predictive of morbidity and mortality during the first year of life. Aim: To study perinatal variables of newborns of mothers living at contrasting altitudinal levels, harboring different degrees of Aymara ancestry. Subjects and Methods: Review of medical records of 5,295 women whose deliveries occurred between February 2004 and August 2010. Information was obtained on place of residence, grouped into two categories: coast (150 to 3,000 m) and high plateau (3,000 to 4,300 m), ancestry was estimated using number of Aymara surnames that were homologated to percentages of Amerindian admixture, gestational age, birth weight, height, head circumference and obstetric variables. Results: Gestational age showed a tendency to increase and birth weight, height and head circumference to decrease with altitude of residence. Only weight reached statistical significance. Women with Aymara ancestry gave birth to children with a significantly higher gestational age, weight and cranial circumference. Conclusions: Altitude of residence is related to a decrease in perinatal variables that proved to be less pronounced in newborns of mothers with a higher degree of Aymara ancestry. Results suggest a genetic adaptation to hypoxia that could be related to candidate genes linked to the capture, transport or utilization of oxygen.

Insulin-like growth factor 1 gene (CA)n repeats and a variable number of tandem repeats of the insulin gene in Brazilian children born small for gestational age

OBJECTIVE: To investigate the influence of (CA)n repeats in the insulin-like growth factor 1 gene and a variable number of tandem repeats of the insulin gene on birth size in children who are small or adequate-sized for gestational age and to correlate these polymorphisms with serum insulin-like growth factor 1 levels and insulin sensitivity in children who are small for gestational age, with and without catch-up growth. PATIENTS AND METHODS: We evaluated 439 infants: 297 that were adequate-sized for gestational age and 142 that were small for gestational age (66 with and 76 without catch-up). The number of (CA)n repeat in the insulin-like growth factor 1 gene and a variable number of tandem repeats in the insulin gene were analyzed using GENESCAN software and polymerase chain reaction followed by enzymatic digestion, respectively. Clinical and laboratory data were obtained from all patients. RESULTS: The height, body mass index, paternal height, target height and insulin-like growth factor 1 serum levels were higher in children who were small for gestational age with catch-up. There was no difference in the allelic and genotypic distributions of both polymorphisms between the adequate-sized and small infants or among small infants with and without catch-up. Similarly, the polymorphisms were not associated with clinical or laboratory variables. CONCLUSION: Polymorphisms of the (CA)n repeats of the insulin-like growth factor 1 gene and a variable number of tandem repeats of the insulin gene, separately or in combination, did not influence pre- or postnatal growth, insulin-like growth factor 1 serum levels or insulin resistance. .

Avances en el diagnóstico de las alteraciones del eje somatotrófico que causan retardo del crecimiento / An update on the diagnosis of growth hormone axis disturbances that cause stunting

Human growth is a complex process regulated by several genes, most of which are unknown. Recently, our knowledge regarding the etiology of genetically determined causes of short stature has greatly increased, so molecular analysis is becoming essential for the diagnosis of growth retardation. The advances in our understanding of the molecular mechanisms involved in the function of the somatotrophic axis have resulted in a dramatic enhancement of our ability to diagnose and treat growth disorders. We hope that in the next few years improved methods for identifying specific abnormalities which cause short stature will expand our ability to diagnose other causes of growth retardation, and reduce the proportion of patients with "idiopathic" short stature.

Analysis of genetic and non-genetic factors that affect the QTc interval in a Mongolian population: the GENDISCAN study

The QTc interval is a complex quantitative trait and a strong prognostic indicator of cardiovascular mortality in general, healthy people. The aim of this study was to identify non-genetic factors and quantitative trait loci that govern the QTc interval in an isolated Mongolian population. We used multiple regression analysis to determine the relationship between the QTc interval and non-genetic factors including height, blood pressure, and the plasma lipid level. Whole genome linkage analyses were performed to reveal quantitative trait loci for the QTc interval with 349 microsatellite markers from 1,080 Mongolian subjects. Among many factors previously known for association with the QTc interval, age, sex, heart rate, QRS duration of electrocardiogram and systolic blood pressure were also found to have influence on the QTc interval. A genetic effect for the QTc interval was identified based on familial correlation with a heritability value of 0.31. In a whole genome linkage analysis, we identified the four potential linkage regions 7q31-34, 5q21, 4q28, and 2q36.

Altura final em criancas com puberdade precoce central: a experiência de um serviço de referência / Final Height in Children with Central Precocious Puberty the experience of a Specialized Center The Experience of a Specialized Center

Introdução: A puberdade precoce central ocorre principalmente devido a ativação precoce do eixo hipotalâmico-hipofisário-gonadal e conseqüentemente ao aumento do hormônios gonadotróficos. A prematura ativação desse eixo não envolve apenas mudanças físicas precoces da puberdade, mas também aceleração do crescimento linear e aceleração da maturação óssea, que leva a fusão das epífises ósseas de maneira prematura e à diminuição da altura final. Objetivo: Identificar a altura final de pacientes que apresentaram Puberdade Precoce Central atendidos no Serviço de Endocrinologia Pediátrica do Hospital Infantil Joana de Gusmão. Métodos: Foram avaliados os registros de pacientes que haviam atingido a AF no período de 1997-2007. As variáveis analisadas foram: sexo, idade cronológica, idade óssea, idade ao diagnóstico, idade ao atingir a altura final, tempo de tratamento até altura final, tempo de acompanhamento até a altura final, tratamento utilizado, altura no início e término do tratamento, altura predita pelo método de Bayley – Pinneau, altura-alvo e altura final ( transformada em escore z). Resultados: Foram incluídos 56 pacientes, 96,4 % do sexo feminino e 90,75 % dos pacientes apresentavam PPC idiopática. Os pacientes masculinos foram tratados com análogo do hormônio liberador de gonadotrofinas por 2,7 anos em média, enquanto que as pacientes femininas foram tratadas durante 3,1 anos. A altura final foi alcançada aos 15,1 anos nos meninos e 14,2 anos nas meninas.Conclusões: A média de altura final foi 171,25 cm no sexo masculino e 160,77 cm no sexo feminino. O escore-z de AF foi de -0,55 desvios padrão da média nos meninos e 0,04 desvios padrão da média nas meninas. A diferença entre altura final e altura alvo foi de -5,25 cm nos meninos e 2,4 cm nas meninas.

Background: Central precocious puberty is mainly due to the precocious activation of hypothalamic-pituitary-gonadal axis leading to an increase of gonadotropic hormones. The premature activation of this axis it involves not only early physical changes of puberty, but also linear growth acceleration and acceleration of bone maturation, which leads to early epiphyseal fusion and short adult height. Objective: To identify final height in central precocious puberty patients treated at Pediatric Endocrinology Service of Hospital Infantil Joana de Gusmão. Methods: The study evaluated the registration of patients that had reached the final height between 1997-2007. Data included sex, chronological age, bone age, age at diagnosis, age at final height, duration of treatment, duration of accompaniment from the start of treatment to final height, treatment used, height at the start and at the end of treatment, predicted height by Bayley – Pinneau method, target height and final height (these are transformed in z-score). Results: Fifty six patients were involved. 96,4 % were female sex and 90,75 % had idiopathic central precocious puberty. The males were treated with Gonadotropin Releasing Hormone Analogue by 2,7 years and females were treated by 3,1 years. Final height was reached at 15,1 years in boys and 14,2 years in girls. Conclusions: Final height average was 171,25 cm in males and 160,77 cm in females. The z-score of final height was -0,55 standard deviation of average in boys and 0,04 standard deviation of average in girls. The difference between final height and target height were -5,25 cm in boys and 2,4 cm in girls.

Síndrome de Aarskog: hallazgos fenotípicos en una cohorte de pacientes / Aarskog syndrome: phenotypic findings in a cohort of patients

Se presentan los hallazgos fenotípicos de 7 pacientes diagnosticados de síndrome de Aarskog en el servicio de Genética del Hospital Pediátrico Docente William Soler. Las características fenotípicas que estuvieron presentes en todos los pacientes fueron el pico de viuda, las extremidades cortas y la braquidactilia. Les siguieron en orden de frecuencia (85 por ciento) la nariz pequeÑa, el puente nasal ancho y el filtrum largo y ancho. Otras dismorfias faciales encontradas (71 por ciento) fueron la frente amplia, las narinas antevertidas, el hipertelorismo, el cuello corto y el surco simiano. Se discute la posibilidad de que exista algún sesgo de detección debido a que el examinador presta mayor atención a la cara que a otros segmentos corporales. La criptorquidia, que distingue y da nombre al síndrome, se encontró en un porcentaje menor de individuos (60 por ciento). En dos casos se encontró hipoplasia renal, hallazgo ocasional en la literatura consultada. En ningún caso se constató retraso mental. Las diferencias fenotípicas halladas pudieran atribuirse a las diferencias moleculares reportadas en la literatura.

The phenotypic fndings of 7 patients who were diagnosed Aarskog syndrome in the Service of Genetics of William Soler Pediatric Teaching Hospital were presented. The phenotypic characteristics appearing in all patients were widow's peak, short extremities and brachydactilia. They were followed in order of frequency (85 percent) by small nose, wide nasal bridge and long and wide filtrum. Other facial dismorphies (71 percent) were wide forehead, anteverted narines, hypertelorism, short neck and simian crease. It is discussed the possibility that there is some bias of detection due to the fact that the examiner pays more attention to the face than to other body segments. Criptorchydia, that distinguishes and gives name to the syndrome, was found in a lower percent of individuals (60 percent). Renal hypoplasia, an occasional finding in the consulted literature, was observed in 2 cases. Mental retardation was not confirmed in any case. The phenoptypic differences detected could be attributed to mollecular differences reported in literature.

Tall stature and poor breast development after estrogen replacement in a hypergonadotrophic hypogonadic patient with a 45,X/46,X,der(X) karyotype with SHOX gene overdosage / Estatura alta e hipodesenvolvimento mamário após reposição estrogênica em paciente com hipogonadismo hipergonadotrófico e cariótipo 45,X/46,X, der(X) com superdosagem do gene SHOX

SHOX is exclusively expressed in the developing distal limb bones of human embryos and in the first and second pharyngeal arches. It works as a promoter for linear growth and as a repressor of growth plate fusion. It was reported, recently, that SHOX overdosage and gonadal estrogen deficiency have led to tall stature due to continued growth. We report, in the present study, a female patient with 45,X/46,X, psu idic(X)(pter→q21::q21→pter) karyotype, tall stature, and hypergonadotrophic hypogonadism without Turner stigmas. She did not present breast development even after long term therapy with high estrogen doses. Fluorescence in situ hybridization depicted the presence of three copies of SHOX gene. Microsatellite studies showed paternal origin of der(X). Further studies in similarly affected patients will clarify if the absence of breast development, despite previous high-dose estrogen treatment, is associated to triple copy of SHOX gene.

O gene SHOX é expresso, exclusivamente, no primeiro e no segundo arcos faríngeos, assim como nas extremidades dos ossos dos membros em embriões humanos. SHOX normalmente atua como um promotor para o crescimento linear e como um repressor do fechamento da placa de crescimento. Recentemente, foi descrito que o excesso da proteína SHOX associada à deficiência estrogênica gonadal leva à estatura alta devido ao contínuo crescimento. Neste estudo descrevemos uma paciente do sexo feminino com cariótipo 45,X/46,X,psu idic(X)(pter→q21::q21→pter), estatura alta, hipogonadismo hipergonadotrófico e sem estigmas de Turner. A paciente não apresentou desenvolvimento de mamas, mesmo depois do tratamento prolongado com altas doses de estrógenos. FISH evidenciou a presença de três cópias do SHOX. Estudo de microssatélites demonstrou a origem paterna do der(X). Estudos futuros em pacientes com semelhanças clínicas esclarecerão se a ausência de desenvolvimento de mamas, apesar do tratamento com altas doses de estrógenos, está associada à tripla cópia do SHOX.

Diferença entre peso e estatura auto-referidos e aferidos para o cálculo do índice de massa corporal e sua relação com a imagem corporal de mulheres de academia de ginástica / Difference between self-reported and actual figures of weights and heights in the determination of the body mass index and its relation to the body image of female gym members

Este estudo investigou a diferença entre peso e estatura auto-referidos, no cálculo do Índice de Massa Corporal (IMC), em relação aos valores aferidos, em alunas de uma academia de ginástica, associando estas diferenças à satisfação corporal das mesmas. O estudo foi realizado com 110 mulheres, que responderam a um questionário de satisfação corporal, informaram o seu peso e estatura e foram medidas e pesadas posteriormente. Entre o grupo estudado, houve subestimação do peso e superestimação da estatura. O IMC, por conseqüência, foi subestimado. Estas distorções foram discretas e não se relacionaram com o nível de satisfação corporal, avalizando assim a utilização de valores auto-referidos em estudos epidemiológicos.

This study has measured the difference between self-reported weight and height for the determination of the Body Mass Index (BMI) compared to the actual figures in female members of a gym, associating those differences to the subjects' body satisfaction level. The survey was conducted on 110 women, who answered a body satisfaction questionnaire, informed their weight and height, and were measured and weighed as well. There was underestimation of the weight and overestimation of the height among the subjects. Consequently, the BMI was also underestimated. There was evidence of slight distortions and those did not relate to the level of body satisfaction, thus endorsing the use of self-reported values in epidemiologic studies.

Baixa estatura por haploinsuficiência do gene SHOX: do diagnóstico ao tratamento / Short stature caused by SHOX gene haploinsufficiency: from diagnosis to treatment

Estudos realizados em pacientes portadores de deleções parciais dos cromossomos sexuais permitiram a caracterização do SHOX, gene localizado na região pseudoautossômica no braço curto dos cromossomos sexuais, fundamental na determinação da altura normal. A perda de uma cópia deste gene na síndrome de Turner (ST) explica dois terços da baixa estatura observada nesta síndrome. A haploinsuficiência do SHOX é detectada em 77 por cento dos pacientes com discondrosteose de Leri-Weill, uma forma comum de displasia esquelética de herança autossômica dominante e em 3 por cento das crianças com baixa estatura idiopática (BEI), tornando os defeitos neste gene a principal causa monogênica de baixa estatura. A medida da altura sentada em relação à altura total (Z da AS/AT para idade e sexo) é uma forma simples de identificar a desproporção corpórea e, associada ao exame cuidadoso do paciente e de outros membros da família, auxilia na seleção de pacientes para o estudo molecular do SHOX. O uso de hormônio de crescimento (GH) está bem estabelecido na ST e em razão da causa comum da baixa estatura com o de crianças com defeitos isolados do SHOX o tratamento destes pacientes com GH é também proposto. Neste artigo será revisado os aspectos clínicos, moleculares e terapêuticos da haploinsuficiência do SHOX.

Studies involving patients with short stature and partial deletion of sex chromosomes identified SHOX gene in the pseudoautosomal region of the X and Y chromosomes. SHOX haploinsufficiency is an important cause of short stature in a diversity of clinical conditions. It explains 2/3 of short stature observed in Turner syndrome (TS) patients. Heterozygous mutations in SHOX are observed in 77 percent of patients with Leri-Weill dyschondrosteosis, a common dominant inherited skeletal dysplasia and in 3 percent of children with idiopathic short stature, indicating that SHOX defects are the most frequent monogenetic cause of short stature. The sitting height/height ratio (SH/H) standard deviation score is a simple way to assess body proportions and together with a careful exam of other family members, effectively selected a group of patients that presented a high frequency of SHOX mutations. Growth hormone treatment of short stature due to TS is well established and considering the common etiology of short stature in patients with isolated defects of SHOX gene, this treatment is also proposed for these patients. Here, we review clinical, molecular and therapeutic aspects of SHOX haploinsufficiency.

Síndrome de Noonan: do fenótipo à terapêutica com hormônio de crescimento / Noonan syndrome: from phenotype to growth hormone therapy

A síndrome de Noonan (SN) é uma síndrome genética comum que constitui importante diagnóstico diferencial em pacientes com baixa estatura, atraso puberal ou criptorquidia. A SN apresenta grande variabilidade fenotípica e é caracterizada principalmente por dismorfismo facial, cardiopatia congênita e baixa estatura. A herança é autossômica dominante com penetrância completa. O diagnóstico é clínico, com base em critérios propostos por van der Burgt, em 1994. Recentemente, diversos genes envolvidos na via de sinalização RAS-MAPK foram identificados como causadores da SN: PTPN11, KRAS, SOS1, RAF1 e MEK1. O tratamento com hormônio de crescimento (hrGH) é proposto para corrigir a baixa estatura observada nestes pacientes. Estudos recentes apontam que pacientes com SN por mutações no gene PTPN11 apresentam pior resposta ao tratamento com hrGH quando comparado com pacientes sem mutações no PTPN11. Este artigo revisará os aspectos clínicos, moleculares e do tratamento da baixa estatura de crianças com SN com hrGH.

Noonan Syndrome (NS) is one of the most common genetic syndromes and it is an important differential diagnosis in children with short stature, delayed puberty and cryptorchidism. NS is characterized by dysmorphic facial features, congenital heart defects and short stature, but there is a great variability in phenotype. NS may occur in a pattern consistent with autosomal dominant inheritance with almost complete penetrance. The diagnosis is based on a clinical score system proposed by van der Burgt e cols. in 1994. In recent years, germline mutations in the components of RAS-MAPK (mitogen activated protein kinase) pathway have been shown to be involved in the pathogenesis of NS. Mutations in PTPN11, KRAS, SOS1, RAF1 e MEK1 can explain 60-70 percent of NS molecular cause. Growth hormone therapy is proposed to correct the short stature observed in these patients. Recent studies suggest that the presence of PTPN11 mutations in patients with NS indicates a reduced growth response to short-term hrGH treatment. In this article, it is reviewed clinical and molecular aspects of NS and hrGH treatment for short stature.

Size of the exon 1-CAG repeats of the androgen receptor gene employed as a molecular marker in the diagnosis of Turner syndrome in girls with short stature

Turner syndrome (TS) is one of the most common chromosomal abnormalities among girls. Complete monosomy of X chromosome is responsible for almost 50% of all cases of TS, and mosaicism and X anomaly are detected in the other half. It has already been demonstrated that early diagnosis of these children allows appropriate growth hormone treatment with better final height prognosis and introduction of estrogen at an ideal chronological age. Sixty-four short-stature girls were selected and the clinical data obtained were birth weight and height, weight and height at the first medical visit and target height. Other clinical data including cardiac and renal abnormalities, otitis, Hashimoto thyroiditis, cubitus valgus, short neck, widely separated nipples, and pigmented nevi were obtained from the patients’ medical records. The aim of the present study was to evaluate the screening of a group of short-stature girls for TS based on the number of CAG repeats of the androgen receptor gene analyzed by GeneScan software. Patient samples with two alleles (heterozygous) were 49/64 (76.5%) and with one allele (homozygous) were 15/64 (23.5%). A karyotype was determined in 30 patients, 9 homozygous and 21 heterozygous. In the homozygous group, 6/9 were 45,X and 3/9 were 46,XX. In the heterozygous group, 17/21 were 46,XX, and 4/21 were TS patients with mosaicism (45,X/46,XX; 45,X/46XiXq; 46XdelXp). The pattern obtained by GeneScan in two patients with mosaicism in the karyotype was an imbalance between the peak heights of the two alleles, suggesting that this imbalance could be present when there is a mosaicism. The frequency of TS abnormalities (18.7%) did not differ between TS and 46,XX girls. Thus, it is important to accurately assess the incidence of TS in growth-retarded girls, even in the absence of other dysmorphisms. In this study, we diagnosed 6 cases of TS 45,X (9.4%) by molecular analysis, with a 100% sensitivity and 85% specificity. This molecular analysis was...