Genome-wide association study of fasting proinsulin, fasting insulin, 2-hour postprandial proinsulin, and 2-hour postprandial insulin in Chinese Han people

Abstract

Introduction:Fasting proinsulin (FPI) and fasting insulin (FI) have been demonstrated to be associated with impaired b-cell function, T2DM, and insulin resistance. This genome-wide association study (GWAS) was performed to contribute to our understanding of the genetic basis of FPI, FI, 2-hour postprandial proinsulin (2hPI), and 2-hour postprandial insulin (2hI) of the pathophysiology of prediabetes in the Chinese population. Material and methods:The levels of fasting plasma glucose (FPG), FPI, FI, 2hPI, and 2hI were examined by an automatic biochemical analyser. The Applied Biosystems TM Axiom TM Precision Medicine Diversity Array, the Gene Titan Multi-Channel instrument, and Axiom Analysis Suite 6.0 Software were used for genotyping. Imputation was performed with IMPUTE 2.0 software from HapMap, 1000 Genomes Phase 3 as a reference panel. Results: Six single nucleotide polymorphisms (SNPs) in DLG1-AS1, SORCS1, and CTAGE11P for FPI, and 27 SNPs in ZNF718, MARCHF2, and HNRNPM for 2hPI reached genome-wide significance. Genome-wide significance was reached for associations of 6 SNPs in KRT71 to FI. Also, 14 SNPs in UBE2U, ABO, and GRID1-AS1 were genome-wide significant in their relationship with 2hI. Among these, the genetic loci of CTAGE11P, MARCHF2, KRT71, and ABO have the strongest association with FPI, 2hPI, FI, and 2hI. Conclusions: The genetic variants of CTAGE11P, MARCHF2, KRT71, and ABO are significantly correlated with FPI, 2hPI, FI, and 2hI, respectively, in Chinese Han people. These genetic variants may serve as new biomarkers for the prevention of prediabetes.