Identification of genetic loci stratified by diabetic status and microRNA related SNPs influencing kidney function in Korean populations

Abstract

Chronic kidney disease (CKD) is characterized by a progressive loss of kidney function over a period of months or years. It is estimated that about 7.2 % of adults over the age of 30 have CKD worldwide. Although one of the major risk factors of CKD is family history, the heritability of CKD is not fully understood. It is also known that the diabetic condition is highly influential on the onset of CKD. To understand the genetic bases of CKD that remain unidentified, we performed genetic association analyses for kidney function-related traits such as blood urea nitrogen (BUN) and albumin in subjects stratified by diabetic status. In the discovery stage of the study, we used genome-wide scan data and clinical data in about 8800 subjects from the Korean Association Resource (KARE) project. Health2 study data comprising about 1800 subjects were used for the replication stage. Our two stage association analyses demonstrated that the LOC105374266 locus (rs9820070) showed strong evidence of association with BUN (P = 8.47 x 10(-14)) in nondiabetic normal subjects (n = similar to 4300). To extend our knowledge of the genetic determinants influencing kidney function, we also analyzed the association between kidney function-related traits and microRNA related variants. For this analysis, miRNA related SNPs were selected from KARE and Health2 cohort genotype data. Our study suggests the potential relevance of miRNA to the kidney function (miR-518b for BUN; miR-146a and miR-1295a for albumin) in Korean populations.