Large-scale gene sequencing studies for complex traits have the potential to identify causal genes with therapeutic implications. We performed gene-based association testing of blood lipid levels with rare (minor allele frequency < 1%) predicted damaging coding variation by using sequence data from >170,000 individuals from multiple ancestries: 97,493 European, 30,025 South Asian, 16,507 African, 16,440 Hispanic/Latino, 10,420 East Asian, and 1,182 Samoan. We identified 35 genes associated with circulating lipid levels; some of these genes have not been previously associated with lipid levels when using rare coding variation from population-based samples.
View Article and Find Full Text PDFProtein-coding genetic variants that strongly affect disease risk can yield relevant clues to disease pathogenesis. Here we report exome-sequencing analyses of 20,791 individuals with type 2 diabetes (T2D) and 24,440 non-diabetic control participants from 5 ancestries. We identify gene-level associations of rare variants (with minor allele frequencies of less than 0.
View Article and Find Full Text PDFTo investigate the genetic basis of type 2 diabetes (T2D) to high resolution, the GoT2D and T2D-GENES consortia catalogued variation from whole-genome sequencing of 2,657 European individuals and exome sequencing of 12,940 individuals of multiple ancestries. Over 27M SNPs, indels, and structural variants were identified, including 99% of low-frequency (minor allele frequency [MAF] 0.1-5%) non-coding variants in the whole-genome sequenced individuals and 99.
View Article and Find Full Text PDFBackground: The Na-H exchanger [NHE] performs an electroneutral uptake of NaCl and water from the lumen of the gastrointestinal tract. There are several distinct NHE isoforms, some of which show an altered expression in the inflammatory bowel diseases (IBD). In this study, we examined a role of NHE-2 in experimental colitis.
View Article and Find Full Text PDFObjective: Type 2 diabetes (T2D) is the primary case of chronic kidney disease (CKD). Inflammation is associated with metabolic dysregulation in patients with T2D and CKD. Tryptophan (TRP) metabolism may have relevance to the CKD outcomes and associated symptoms.
View Article and Find Full Text PDFBackground: The Genetic Analysis Workshops (GAW) are a forum for development, testing, and comparison of statistical genetic methods and software. Each contribution to the workshop includes an application to a specified data set. Here we describe the data distributed for GAW19, which focused on analysis of human genomic and transcriptomic data.
View Article and Find Full Text PDFBackground/aim: Toll-like receptor 4 (TLR4) is one of the regulators of the innate immune response. Genetic variations in TLR4 have been associated with inflammatory diseases, including type 2 diabetes. However, to our knowledge, there are no reports on the role of variations in TLR4 in chronic kidney disease susceptibility.
View Article and Find Full Text PDFThe genetic architecture of common traits, including the number, frequency, and effect sizes of inherited variants that contribute to individual risk, has been long debated. Genome-wide association studies have identified scores of common variants associated with type 2 diabetes, but in aggregate, these explain only a fraction of the heritability of this disease. Here, to test the hypothesis that lower-frequency variants explain much of the remainder, the GoT2D and T2D-GENES consortia performed whole-genome sequencing in 2,657 European individuals with and without diabetes, and exome sequencing in 12,940 individuals from five ancestry groups.
View Article and Find Full Text PDFBackground: The presence of population structure in a sample may confound the search for important genetic loci associated with disease. Our four samples in the Family Investigation of Nephropathy and Diabetes (FIND), European Americans, Mexican Americans, African Americans, and American Indians are part of a genome- wide association study in which population structure might be particularly important. We therefore decided to study in detail one component of this, individual genetic ancestry (IGA).
View Article and Find Full Text PDFDiabetic kidney disease (DKD) is the most common etiology of chronic kidney disease (CKD) in the industrialized world and accounts for much of the excess mortality in patients with diabetes mellitus. Approximately 45% of U.S.
View Article and Find Full Text PDFBackground: The estimated glomerular filtration rate (eGFR) is a well-known measure of kidney function and is commonly used for the diagnosis and management of patients with chronic kidney disease. The inter-individual variation in eGFR has significant genetic component. However, the identification of underlying genetic susceptibility variants has been challenging.
View Article and Find Full Text PDFObjective: Estimated glomerular filtration rate (eGFR), a measure of kidney function, is heritable, suggesting that genes influence renal function. Genes that influence eGFR have been identified through genome-wide association studies. However, family-based linkage approaches may identify loci that explain a larger proportion of the heritability.
View Article and Find Full Text PDFThe rising global epidemic of diabetic nephropathy (DN) will likely lead to increase in the prevalence of cardiovascular morbidity and mortality posing a serious burden for public health care. Despite greater understanding of the etiology of diabetes and the development of novel treatment strategies to control blood glucose levels, the prevalence and incidence rate of DN is increasing especially in minority populations including Mexican-Americans. Mexican-Americans with type 2 diabetes (T2DM) are three times more likely to develop microalbuminuria, and four times more likely to develop clinical proteinuria compared to non-Hispanic whites.
View Article and Find Full Text PDFThe objective of this study is to identify and characterize the genetic variants related to the glomerular filtration rate (GFR) linkage on 2q37. Of the positional candidate genes, we selected IRS1 and resequenced its 2-kb promoter region and exons for sequence variants in 32 subjects. A total of 11 single nucleotide polymorphisms (SNPs) were identified.
View Article and Find Full Text PDFThe incidence of diabetic nephropathy (DN) is growing rapidly worldwide as a consequence of the rising prevalence of Type 2 diabetes mellitus (T2DM). Among U.S.
View Article and Find Full Text PDFHypertension affects one billion people and is a principal reversible risk factor for cardiovascular disease. Pseudohypoaldosteronism type II (PHAII), a rare Mendelian syndrome featuring hypertension, hyperkalaemia and metabolic acidosis, has revealed previously unrecognized physiology orchestrating the balance between renal salt reabsorption and K(+) and H(+) excretion. Here we used exome sequencing to identify mutations in kelch-like 3 (KLHL3) or cullin 3 (CUL3) in PHAII patients from 41 unrelated families.
View Article and Find Full Text PDFBackground: Evidence for linkage of albuminuria to GABRB3 marker region on chromosome 15q12 was previously reported in Mexican Americans. The objective of this study is to scan a positional candidate gene, Transient Receptor Potential cation channel, subfamily M 1 (TRPM1), for genetic variants that may contribute to the variation in albumin-to-creatinine ratio (ACR).
Methods: To identify the sequence variants, the exons and 2 kb putative promoter region of TRPM1 were PCR amplified and sequenced in 32 selected individuals.
Objective: Human 8-oxoguanine glycosylase 1 (OGG1) excises oxidatively damaged promutagenic base 8-oxoguanine, a lesion previously observed in a rat model of type 2 diabetes (T2DM). The objective of the present study is to determine whether genetic variation in OGG1 is associated with type 2 diabetes (T2DM) in a Mexican American cohort.
Methods: Ten SNPs including two tagging SNPs (rs1052133, rs2072668) across the OGG1 gene region were selected from the Hapmap database and genotyped in the entire cohort (n = 670; 29% diabetes; 39 families) by TaqMan assay.
Background: Previous studies have shown that in addition to environmental influences, type 2 diabetes mellitus (T2DM) has a strong genetic component. The goal of the current study is to identify regions of linkage for T2DM in ethnically diverse populations.
Methods: Phenotypic and genotypic data were obtained from African American (AA; total number of individuals [N] = 1004), American Indian (AI; N = 883), European American (EA; N = 537), and Mexican American (MA; N = 1634) individuals from the Family Investigation of Nephropathy and Diabetes.
Several novel genes that are up-regulated in the kidney in diabetes have been identified including GREM1, which encodes gremlin 1. GREM1 maps to human chromosome 15q12, a region previously found to be linked to albumin to creatinine ratio (ACR) in Mexican Americans. The objective of this study is to investigate whether genetic variants in GREM1, a positional candidate gene, contribute to variation in ACR.
View Article and Find Full Text PDFBackground/aims: Genetic polymorphisms in the paraoxonase 2 (PON2) gene are thought to alter its activity and contribute to the development of cardiovascular and renal disease risk. The purpose of this study is to determine whether the Arg148Gly, Cys311Ser and rs12794795 polymorphisms of PON2 examined previously by others, are associated with type 2 diabetes (T2DM), and subclinical measures of cardiovascular and renal disease risk in Mexican Americans.
Methods: Study participants (n = 848; 21 families) were genotyped for the three polymorphisms by TaqMan assay.
The T-786C, Glu298Asp, and 27 bp variable number of tandem repeats (27 bp-VNTR-a/b) polymorphsims of the endothelial nitric oxide synthase (eNOS) gene are thought to alter nitric oxide production and contribute to the development of vascular and renal disease risk. The objective of this study is to investigate whether these three polymorphisms examined previously by others are associated with cardiovascular and renal disease risk in Mexican Americans. Study participants (N = 848; 21 families) were genotyped for T-786C, Glu298Asp, and 27 bp-VNTR-a/b polymorphisms by PCR followed by restriction digestion.
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