Clinical spectrum of Transthyretin amyloidogenic mutations among diverse population origins.

PURPOSE: Coding mutations in the Transthyretin (TTR) gene cause a hereditary form of amyloidosis characterized by a complex genotype-phenotype correlation with limited information regarding differences among worldwide populations. METHODS: We compared 676 diverse individuals carrying TTR amyloidogenic mutations (rs138065384, Phe44Leu; rs730881165, Ala81Thr; rs121918074, His90Asn; rs76992529, Val122Ile) to 12,430 non-carriers matched by age, sex, and genetically-inferred ancestry to assess their clinical presentations across 1,693 outcomes derived from electronic health records in UK biobank. RESULTS: In individuals of African descent (AFR), Val122Ile mutation was linked to multiple outcomes related to the circulatory system (fold-enrichment = 2.96, p = 0.002) with the strongest associations being cardiac congenital anomalies (phecode 747.1, p = 0.003), endocarditis (phecode 420.3, p = 0.006), and cardiomyopathy (phecode 425, p = 0.007). In individuals of Central-South Asian descent (CSA), His90Asn mutation was associated with dermatologic outcomes (fold-enrichment = 28, p = 0.001). The same TTR mutation was linked to neoplasms in European-descent individuals (EUR, fold-enrichment = 3.09, p = 0.003). In EUR, Ala81Thr showed multiple associations with respiratory outcomes related (fold-enrichment = 3.61, p = 0.002), but the strongest association was with atrioventricular block (phecode 426.2, p = 2.81 × 10- 4). Additionally, the same mutation in East Asians (EAS) showed associations with endocrine-metabolic traits (fold-enrichment = 4.47, p = 0.003). In the cross-ancestry meta-analysis, Val122Ile mutation was associated with peripheral nerve disorders (phecode 351, p = 0.004) in addition to cardiac congenital anomalies (fold-enrichment = 6.94, p = 0.003). CONCLUSIONS: Overall, these findings highlight that TTR amyloidogenic mutations present ancestry-specific and ancestry-convergent associations related to a range of health domains. This supports the need to increase awareness regarding the range of outcomes associated with TTR mutations across worldwide populations to reduce misdiagnosis and delayed diagnosis of TTR-related amyloidosis.

Microparticles from dental calculus disclose paleoenvironmental and palaeoecological records.

Plants have always represented a key element in landscape delineation. Indeed, plant diversity, whose distribution is influenced by geographic/climatic variability, has affected both environmental and human ecology. The present contribution represents a multi-proxy study focused on the detection of starch, pollen and non-pollen palynomorphs in ancient dental calculus collected from pre-historical individuals buried at La Sassa and Pila archaeological sites (Central Italy). The collected record suggested the potential use of plant taxa by the people living in Central Italy during the Copper-Middle Bronze Age and expanded the body of evidence reported by previous palynological and palaeoecological studies. The application of a microscopic approach provided information about domesticated crops and/or gathered wild plants and inferred considerations on ancient environments, water sources, and past health and diseases. Moreover, the research supplied data to define the natural resources (e.g., C4-plant intake) and the social use of the space during that period. Another important aspect was the finding of plant clues referable to woody habitats, characterised by broad-leaved deciduous taxa and generally indicative of a warm-temperate climate and grassy vegetation. Other unusual records (e.g., diatoms, brachysclereids) participated in defining the prehistoric ecological framework. Thus, this work provides an overview on the potential of the human dental calculus analysis to delineate some features of the ancient plant ecology and biodiversity.

Cross-ancestry genome-wide association studies identified heterogeneous loci associated with differences of allele frequency and regulome tagging between participants of European descent and other ancestry groups from the UK Biobank.

To investigate cross-ancestry genetics of complex traits, we conducted a phenome-wide analysis of loci with heterogeneous effects across African, Admixed-American, Central/South Asian, East Asian, European and Middle Eastern participants of the UK Biobank (N = 441 331). Testing 843 phenotypes, we identified 82 independent genomic regions mapping variants showing genome-wide significant (GWS) associations (P < 5 × 10-8) in the trans-ancestry meta-analysis and GWS heterogeneity among the ancestry-specific effects. These included (i) loci with GWS association in one ancestry and concordant but heterogeneous effects among the other ancestries and (ii) loci with a GWS association in one ancestry group and an experiment-wide significant discordant effect (P < 6.1 × 10-4) in at least another ancestry. Since the trans-ancestry GWS associations were mostly driven by the European ancestry sample size, we investigated the differences of the allele frequency (ΔAF) and linkage disequilibrium regulome tagging (ΔLD) between European populations and the other ancestries. Within loci with concordant effects, the degree of heterogeneity was associated with European-Middle Eastern ΔAF (P = 9.04 × 10-6) and ΔLD of European populations with respect to African, Admixed-American and Central/South Asian groups (P = 8.21 × 10-4, P = 7.17 × 10-4 and P = 2.16 × 10-3, respectively). Within loci with discordant effects, ΔAF and ΔLD of European populations with respect to African and Central/South Asian ancestries were associated with the degree of heterogeneity (ΔAF: P = 7.69 × 10-3 and P = 5.31 × 10-3, ΔLD: P = 0.016 and P = 2.65 × 10-4, respectively). Considering the traits associated with cross-ancestry heterogeneous loci, we observed enrichments for blood biomarkers (P = 5.7 × 10-35) and physical appearance (P = 1.38 × 10-4). This suggests that these specific phenotypic classes may present considerable cross-ancestry heterogeneity owing to large allele frequency and LD variation among worldwide populations.

Epigenomic Profiles of African-American Transthyretin Val122Ile Carriers Reveals Putatively Dysregulated Amyloid Mechanisms.

BACKGROUND: The Val122Ile mutation in Transthyretin (TTR) gene causes a rare, difficult to diagnose hereditary form of cardiac amyloidosis. This mutation is most common in the United States and mainly present in people of African descent. The carriers have an increased risk of congestive heart failure, peripheral edema, and several other noncardiac phenotypes such as carpal tunnel syndrome, and arthroplasty which are top reasons for ambulatory/outpatient surgeries (OSs) in the country. METHODS: We conducted first-ever epigenome-wide association study using the Illumina's EPIC array, in Val122Ile carriers of African descent for heart disease and multiple OSs-an early disease indicator. Differential methylation across genome wide cytosine-phosphate guanine (CpG) sites was tested between carriers with and without heart disease and OS. Significant CpG sites were investigated for cis-mQTLs loci, followed by gene ontology and protein-protein interaction network. We also investigated the significant CpG sites in a secondary cohort of carriers for replication. RESULTS: Five differentially methylated sites (P≤2.1×10-8) in genes-FAM129B, SKI, WDR27, GLS, and an intergenic site near RP11-550A5.2, and one differentially methylated region containing KCNA6 and GALNT3 (P=1.1×10-12) were associated with heart disease. For OS, we observe 4 sites-2 sites in UBE2E3 and SEC14L5, and other 2 in intergenic regions (P≤1.8×10-7) and 3 regions overlapping SH3D21, EVA1B, LTB4R2, and CIDEB (P≤3.9×10-7). Functional protein-interaction module analysis identified ABCA1 (P=0.001) for heart disease. Six cis-mQTLs were associated with one of the significant CpG sites (FAM129B; P=4.1×10-24). We replicated 2 CpG sites (cg18546846 and cg06641417; P<0.05) in an external cohort of biopsy-confirmed cases of TTR (transthyretin) amyloidosis. The genes identified are involved in transport and clearance of amyloid deposits (GLS, ABCA1, FAM129B); cardiac fibrosis (SKI); and muscle tissue regulation (SKI, FAM129B). CONCLUSIONS: These findings highlight the link between a complex amyloid circuit and diverse symptoms of Val122Ile.

Epigenetic profiling of Italian patients identified methylation sites associated with hereditary transthyretin amyloidosis.

Hereditary transthyretin (TTR) amyloidosis (hATTR) is a rare life-threatening disorder caused by amyloidogenic coding mutations located in TTR gene. To understand the high phenotypic variability observed among carriers of TTR disease-causing mutations, we conducted an epigenome-wide association study (EWAS) assessing more than 700,000 methylation sites and testing epigenetic difference of TTR coding mutation carriers vs. non-carriers. We observed a significant methylation change at cg09097335 site located in Beta-secretase 2 (BACE2) gene (standardized regression coefficient = -0.60, p = 6.26 × 10-8). This gene is involved in a protein interaction network enriched for biological processes and molecular pathways related to amyloid-beta metabolism (Gene Ontology: 0050435, q = 0.007), amyloid fiber formation (Reactome HSA-977225, q = 0.008), and Alzheimer's disease (KEGG hsa05010, q = 2.2 × 10-4). Additionally, TTR and BACE2 share APP (amyloid-beta precursor protein) as a validated protein interactor. Within TTR gene region, we observed that Val30Met disrupts a methylation site, cg13139646, causing a drastic hypomethylation in carriers of this amyloidogenic mutation (standardized regression coefficient = -2.18, p = 3.34 × 10-11). Cg13139646 showed co-methylation with cg19203115 (Pearson's r2 = 0.32), which showed significant epigenetic differences between symptomatic and asymptomatic carriers of amyloidogenic mutations (standardized regression coefficient = -0.56, p = 8.6 × 10-4). In conclusion, we provide novel insights related to the molecular mechanisms involved in the complex heterogeneity of hATTR, highlighting the role of epigenetic regulation in this rare disorder.

Phenome-wide association study of TTR and RBP4 genes in 361,194 individuals reveals novel insights in the genetics of hereditary and wildtype transthyretin amyloidoses.

Transthyretin (TTR) gene has a causal role in a hereditary form of amyloidosis (ATTRm) and is potentially involved in the risk of wild-type transthyretin amyloidosis (ATTRwt). To understand the genetics of ATTRm and ATTRwt, we conducted a phenome-wide association study of TTR gene in 361,194 participants of European descent testing coding and non-coding variants. Among the 382 clinically relevant phenotypes tested, TTR non-coding variants were associated with 26 phenotypic traits after multiple testing correction. These included signs related to both ATTRm and ATTRwt such as chronic ischaemic heart disease (rs140226130, p = 2.00 × 10-6), heart failure (rs73956431, p = 2.74 × 10-6), atrial fibrillation (rs10163755, p = 4.63 × 10-6), dysphagia (rs2949506, p = 3.95 × 10-6), intestine diseases (rs970866, p = 7.14 × 10-6) and anxiety (rs554521234, p = 8.85 × 10-6). Consistent results were observed for TTR disease-causing mutation Val122Ile (rs76992529) with respect to carpal tunnel syndrome (p = 6.41 × 10-6) and mononeuropathies of upper limbs (p = 1.22 × 10-5). Sex differences were also observed in line with ATTRm and ATTRwt epidemiology. Additionally, we explored possible modifier genes related to TTR function, observing convergent associations of RBP4 variants with the clinical phenotypes associated with TTR locus. In conclusion, we provide novel insights regarding the molecular basis of ATTRm and ATTRwt based on large-scale cohort, expanding our understanding of the phenotypic spectrum associated with TTR gene variation.

Effect of the GSTM1 gene deletion on glycemic variability, sympatho-vagal balance and arterial stiffness in patients with metabolic syndrome, but without diabetes.

AIMS: An increased rate of cerebrovascular complications in patients with metabolic syndrome (MetS) has been reported. Previous studies demonstrated an association between glycemic variability (GV) and cerebrovascular reactivity (CRV) in MetS, thus suggesting a putative role of GV on cerebrovascular events. Although the pathophysiological mechanism linking GV to damage is still to be elucidated, evidence suggests oxidative stress plays a crucial role. Since functional variants in glutathione S-transferases (GST) genes modulate the cellular detoxification processes, the aim of this study was to elucidate the involvement of GSTs in MetS and investigating the correlation with GV, arterial stiffness, and sympatho-vagal (SV) balance. METHODS: A hundred metabolic syndrome patients without diabetes underwent GST gene polymorphism analysis and a sub-sample 36 patients were randomly selected to investigate the correlation between GST gene polymorphisms and GV, and sympatho-vagal (SV) balance and arterial stiffness. RESULTS: GSTM1 showed a significant association with several GV, arterial stiffness, and SV balance indexes. In particular, the GSTM1 deletion positively correlates with lower values of these indexes when compared to the presence of the gene. CONCLUSIONS: Therefore, we suggested a global influence of GSTM1 deletion on the GV, arterial stiffness, and SV balance pathways in MetS patients, probably also interacting with AMP-activated protein kinase (AMPK) regulation. Our novel findings indicate GSTM1 could be a risk locus in MetS development and shed light novel scenarios on the role of glucose fluctuations in neurological impairments.

Non-coding variants contribute to the clinical heterogeneity of TTR amyloidosis.

Coding mutations in TTR gene cause a rare hereditary form of systemic amyloidosis, which has a complex genotype-phenotype correlation. We investigated the role of non-coding variants in regulating TTR gene expression and consequently amyloidosis symptoms. We evaluated the genotype-phenotype correlation considering the clinical information of 129 Italian patients with TTR amyloidosis. Then, we conducted a re-sequencing of TTR gene to investigate how non-coding variants affect TTR expression and, consequently, phenotypic presentation in carriers of amyloidogenic mutations. Polygenic scores for genetically determined TTR expression were constructed using data from our re-sequencing analysis and the GTEx (Genotype-Tissue Expression) project. We confirmed a strong phenotypic heterogeneity across coding mutations causing TTR amyloidosis. Considering the effects of non-coding variants on TTR expression, we identified three patient clusters with specific expression patterns associated with certain phenotypic presentations, including late onset, autonomic neurological involvement, and gastrointestinal symptoms. This study provides novel data regarding the role of non-coding variation and the gene expression profiles in patients affected by TTR amyloidosis, also putting forth an approach that could be used to investigate the mechanisms at the basis of the genotype-phenotype correlation of the disease.

Population diversity of the genetically determined TTR expression in human tissues and its implications in TTR amyloidosis.

BACKGROUND: Transthyretin (TTR) amyloidosis is a hereditary disease with a complex genotype-phenotype correlation. We conducted a literature survey to define the clinical landscape of TTR amyloidosis across populations worldwide. Then, we investigated whether the genetically determined TTR expression differs among human populations, contributing to the differences observed in patients. Polygenic scores for genetically determined TTR expression in 14 clinically relevant tissues were constructed using data from the GTEx (Genotype-Tissue Expression) project and tested in the samples from the 1,000 Genomes Project. RESULTS: We observed differences among the ancestral groups and, to a lesser extent, among the investigated populations within the ancestry groups. Scandinavian populations differed in their genetically determined TTR expression of skeletal muscle tissue with respect to Southern Europeans (p = 6.79*10-6). This is in line with epidemiological data related to Swedish and Portuguese TTR Val30Met endemic areas. Familial amyloidotic cardiomyopathy (TTR deposits occur primarily in heart tissues) presents clinical variability among human populations, a finding that agrees with the among-ancestry diversity of genetically determined TTR expression in heart tissues (i.e., Atrial Appendage p = 4.55*10-28; Left Ventricle p = 6.54*10-35). CONCLUSIONS: Genetically determined TTR expression varied across human populations. This might contribute to the genotype-phenotype correlation of TTR amyloidosis.

Explorative genetic association study of GSTT2B copy number variant in complex disease risks.

BACKGROUND: Glutathione S-transferases (GSTs) are the main phase II enzymes involved in cellular detoxification. Through phase I and phase II detoxification reactions, the cell is able to detoxify endogenous and exogenous toxic compounds. AIMS: This study focused attention on the GSTT2B copy number variant (CNV) in order to explore its involvement in the genetic pre-disposition to asthma, Alzheimer's disease (AD), allergic rhinitis (AR), essential hypertension (EH), hypothyroidism and recurrent miscarriage (RM). METHODS: The study population consists of 1225 individuals divided into six case-control groups. The genotyping of the GSTT2B CNV was performed by using a duplex-PCR. Odds Ratios (ORs) were calculated, adjusting for the confounding variables, to estimate the association between GSTT2B CNV and the disease status. RESULTS: The χ(2)-test and ORs did not show any association between this genetic marker and pathological phenotypes. CONCLUSION: The data highlights that GSTT2B CNV is not associated with the investigated complex diseases in Italian patients. However, further investigations are necessary to replicate these findings in larger sample sizes and to explore other health-related phenotypes.

GSTA1 gene variation associated with gestational hypertension and its involvement in pregnancy-related pathogenic conditions.

OBJECTIVE(S): Glutathione S-transferases (GSTs) are the main phase II enzymes involved in the cellular detoxification. Through phase I and phase II detoxification reactions, the cell is able to detoxify endogenous and exogenous toxic compounds. In this study, we focused our attention on the GSTA1*-69C/T gene polymorphism (rs3957357) in order to explore its involvement in the genetic predisposition to gestational hypertension (GH). STUDY DESIGN: The case-control population consists of 195 subjects. The genotyping of the GSTA1*-69C/T was performed by using an RFLP-PCR technique. We calculated odds ratios (ORs), adjusted for the confounding variables, to estimate the association between GSTA1 and GH. RESULTS: Significant allelic differences in GSTA1*-69C/T are present between GH women and pregnant women without cardiovascular complications (p<0.05). Specifically, we observed that the dominant genetic model best explains the observed genetic association, according to the Akaike information criterion and the Bayesian information criterion. CONCLUSION(S): Our study highlighted a significant association between the GSTA1 gene and the risk of GH in Italian patients. In particular, the -69C/T variant was significantly associated with disease risk. Since previous studies indicated that this GSTA1 polymorphism is associated with different pregnancy-related conditions, our finding supports the notion that GSTA1 may play a key role during pregnancy.

Most recent common ancestor of TTR Val30Met mutation in Italian population and its potential role in genotype-phenotype correlation.

INTRODUCTION: Transthyretin (TTR)-related amyloidosis is characterized by autosomal transmission of amyloidogenic mutated TTR. Val30Met is one of the most common amyloidogenic TTR mutations, showing a worldwide distribution with phenotypic heterogeneity among human populations. Multiple founder mutations for Val30Met foci have been hypothesized and the different origins may explain the phenotypic variability. The aim of our study is to determine the origin of Italian Val30Met and to analyze the genetic relationship of other Val30Met foci. METHODS: We analyzed the origin of Italian Val30Met through 11 microsatellite markers around the TTR gene in 29 patients and 34 healthy controls. RESULTS: Our genetic analysis showed an estimated age of origin of 34-36 generations ago for the Italian Val30Met. Comparing Italian Val30Met haplotypes with those from Sweden and Portugal highlights relevant differences that seem to be consistent with an independent origin of Italian Val30Met mutation. This genetic evidence agrees with the disease phenotypic variation in these populations. DISCUSSION AND CONCLUSIONS: Italian Val30Met mutation should have originated before the Portuguese and Swedish Val30Met ones (which arose through independent mutational events). This indicates a genetic diversity in the surrounding regions of three different Val30Met mutations, supporting the hypothesis that TTR non-coding regions may contribute to phenotypic heterogeneity.

Deletion polymorphism of GSTT1 gene as protective marker for allergic rhinitis.

BACKGROUND AND AIMS: Allergic rhinitis (AR) is one of the most common respiratory diseases among human populations. Strong evidence suggests that genetic predisposition and environmental factors could contribute to the development of this complex disease. Glutathione S-transferases (GSTs) are biomarkers of inflammation and oxidative stress. These phase II enzymes play a significant role in detoxifying xenobiotic compounds. To analyze the role of GST gene polymorphisms in AR pathogenesis in a case-control population of 103 patients affected by AR and 200 healthy non-allergic subjects. METHODS: We screened genomic DNA extracted from buccal cells for GSTM1 positive/null, GSTP1*I105V (rs1695) and GSTT1 positive/null polymorphisms. The X(2) -test, odds ratio (OR) and logistic regression were used as statistical analyses. RESULTS: Significant differences in null genotype distribution between AR patients (13%) and healthy controls (30%) were found for the GSTT1 null genotype (OR = 0.30, 95% confidence interval = 0.14-0.65; P = 0.001). GSTM1 and GSTP1 polymorphisms did not show any significant results. CONCLUSION: Our data indicated that GSTT1 may be a susceptibility locus for AR. Specifically, the positive/null polymorphism of GSTT1 may be involved in an oxidative stress-related mechanism that may enhance pathogenic pathways related to AR. Moreover, beside GSTT1, this deletion polymorphism affects also another gene potentially related to AR phenotype, LOC391322. This gene belongs to MIF (macrophage migration inhibitory factor) gene family and several studies indicated the role of this gene in several immunology-related phenotypes. Therefore, two different scenarios may explain the observed genetic association.

Haplotype differences for copy number variants in the 22q11.23 region among human populations: a pigmentation-based model for selective pressure.

Two gene clusters are tightly linked in a narrow region of chromosome 22q11.23: the macrophage migration inhibitory factor (MIF) gene family and the glutathione S-transferase theta class. Within 120 kb in this region, two 30-kb deletions reach high frequencies in human populations. This gives rise to four haplotypic arrangements, which modulate the number of genes in both families. The variable patterns of linkage disequilibrium (LD) between these copy number variants (CNVs) in diverse human populations remain poorly understood. We analyzed 2469 individuals belonging to 27 human populations with different ethnic origins. Then we correlated the genetic variability of 22q11.23 CNVs with environmental variables. We confirmed an increasing strength of LD from Africa to Asia and to Europe. Further, we highlighted strongly significant correlations between the frequency of one of the haplotypes and pigmentation-related variables: skin color (R(2)=0.675, P<0.001), distance from the equator (R(2)=0.454, P<0.001), UVA radiation (R(2)=0.439, P<0.001), and UVB radiation (R(2)=0.313, P=0.002). The fact that all MIF-related genes are retained on this haplotype and the evidences gleaned from experimental systems seem to agree with the role of MIF-related genes in melanogenesis. As such, we propose a model that explains the geographic and ethnic distribution of 22q11.23 CNVs among human populations, assuming that MIF-related gene dosage could be associated with adaptation to low UV radiation.

In silico analysis of TTR gene (coding and non-coding regions, and interactive network) and its implications in transthyretin-related amyloidosis.

INTRODUCTION: Transthyretin (TTR)-related amyloidosis is a life-threatening disease. Currently, several questions about the pathogenic mechanisms of TTR-related amyloidosis remain unanswered. METHODS: We have investigated various TTR-related issues using different in silico approaches. RESULTS: Using an amino acid similarity-based analysis, we have indicated the most relevant TTR secondary structures in determining mutation impact. Our amyloidogenic propensity analysis of TTR missense substitutions has highlighted a similar pattern for wild-type and mutated TTR amino ß acid sequences. However, some mutations present differences with respect to the general distribution. We have identified non-coding variants in cis-regulatory elements of the TTR gene, and our analysis on V122I-related haplotypes has indicated differences in non-coding regulatory variants, suggesting differences among V122I carriers. The analysis of methylation status indicated CpG sites that may affect TTR expression. Finally, our interactive network analysis revealed functional partners of TTR that may play a modifier role in the pathogenesis of TTR-related amyloidosis. DISCUSSION AND CONCLUSION: Our data provided new insights into the pathogenesis of TTR-related amyloidosis that, if they were to be confirmed through experimental investigations, could significantly improve our understanding of the disease.

Functional variability of glutathione S-transferases in Basque populations.

OBJECTIVES: Glutathione S-transferases (GSTs) are enzymes involved in Phase II reactions. They play a key role in cellular detoxification. Various studies have shown that genes coding for the GST are highly polymorphic and some of these variants are directly associated with a decrease of enzyme activity making individuals more susceptible to different clinical phenotypes. The aim of this study is to investigate the genetic variability of GST genes among human populations. We have focused our attention on the polymorphic variants of the GSTA1, GSTM1, GSTO1, GSTO2, GSTP1, GSTT1, and GSTT2B genes. METHODS: These polymorphisms were analyzed in a whole sample of 151 individuals: 112 autochthonous Navarrese Basques, and 39 non-autochthonous Navarrese Basques. DNA extraction from plasma was performed by using the phenol:chloroform:isoamylic alcohol method. Genotyping of the gene polymorphisms was performed by PCR Multiplex and the PCR-RFLP method. We applied correspondence analysis and built frequency-maps to compare the genetic structure in worldwide populations. RESULTS: Our results were compared with data available on the Human Genome Diversity Project (HGDP) and on the 1,000 Genomes Project to obtain information on the functional variability of GSTs in Basques. Our data indicated that Basque communities showed a higher differentiation of certain functional GST variants (i.e., GSTM1-positive/null genotype, GSTP1*I105V, and GSTT2B*1/0) than other European and Mediterranean populations. CONCLUSIONS: This might account for epidemiological differences in the predisposition to diseases and drug response among Basques and could be used to design and interpret genetic association studies for this particular population.

Human pharmacogenomic variation of antihypertensive drugs: from population genetics to personalized medicine.

AIM: To investigate the human pharmacogenetic variation related to antihypertensive drugs, providing a survey of functional interpopulation differences in hypertension pharmacogenes. MATERIALS & METHODS: The study was divided into two stages. In the first stage, we analyzed 1249 variants located in 57 hypertension pharmacogenes. This first-stage analysis confirmed that geographic origin strongly affects hypertension pharmacogenomic variation and that 31 pharmacogenes are geographically differentiated. In the second stage, we focused our attention on the ethnic-differentiated pharmacogenes, investigating 55,521 genetic variants. In silico analyses were performed to predict the effect of genetic variation. RESULTS: Our analyses indicated functional interpopulation differences, suggesting insight into the mechanisms of antihypertensive drug response. Moreover, our data suggested that rare variants mainly determine the functionality of genes related to antihypertensive drugs. CONCLUSION: Our study provided important knowledge about the genetics of the antihypertensive drug response, suggesting that next-generation sequencing technologies may develop reliable pharmacogenetic tests for antihypertensive drugs.

GSTO1 uncommon genetic variants are associated with recurrent miscarriage risk.

OBJECTIVE: To explore the role of the GSTO1 gene in the pathogenesis of recurrent miscarriage (RM). DESIGN: Genetic association study. SETTING: Rome, Italy. PATIENT(S): 123 women with RM and 130 women without pregnancy complications. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Genotyping of two single nucleotide polymorphisms (A140D and E208K) and a 3-bp deletion (E155del) of the GSTO1 gene. RESULT(S): We found a statistically significant association between GSTO1*E208K variants and RM risk. Specifically, we identified this uncommon genetic variant only in women with RM. None of the women with physiologic pregnancies were carriers of K208 allele. CONCLUSION(S): GSTO1 has a role in detoxification metabolism, and we hypothesize that a functional variation of GSTO1 is a RM risk factor that interacts with environmental conditions.

GSTA1*-69C/T and GSTO2*N142D as asthma- and allergy-related risk factors in Italian adult patients.

1. Asthma and allergies are characterized by variable and subjective symptoms influenced by many genes, molecular mechanisms and environmental factors. The presence of inflammation and oxidative stress in the airways are important biochemical features of asthma and respiratory allergies. Glutathione S-transferase (GSTs) enzymes play an important role in cellular protection against inflammation, and functional genetic polymorphisms in GST genes show a significant association with asthma and allergy risk. Specifically, our previous study on asthmatic children highlighted GSTA1 and GSTO2 as novel susceptibility loci for asthma. 2. In the present study we focused our attention on GSTA1*-69C/T (rs3957357) and GSTO2*N142D (rs156697) polymorphisms to confirm our previous results in an independent adult study population and to clarify whether GSTA1 and GSTO2 gene polymorphisms are involved in a non-discriminative pathway towards asthma and respiratory allergy. 3. To accomplish this, we recruited 103 patients with respiratory allergies, 199 patients with asthma and 200 healthy controls. Genomic DNA extracted from buccal cells was screened for GSTA1*-69C/T and GSTO2*N142D single nucleotide polymorphisms. 4. The GSTA1*-69T and GSTO2*D142 variants are both associated with a significantly increased risk of asthma, whereas only GSTA1*-69C/T is significantly associated with allergies. These outcomes confirm the involvement of GSTO2 loci in asthma and suggest that GSTA1 is a common risk factor for asthma and allergies.