Association of type 2 diabetes susceptibility loci with peripheral nerve function in a Chinese population with diabetes

AIMS/INTRODUCTION: Previous studies have suggested a possible relationship between type 2 diabetes mellitus susceptibility loci and diabetic complications. The present study aimed to investigate the associations between type 2 diabetes mellitus loci with peripheral nerve function in a Chinese population with type 2 diabetes mellitus. MATERIALS AND METHODS: A total of 1,900 type 2 diabetes mellitus patients were recruited in the study. We selected ten single nucleotide polymorphisms (SNPs) from ten type 2 diabetes mellitus susceptibility genes previously confirmed in Chinese patients. Genotyping was carried out by using a MassARRAY Compact Analyzer. Peripheral nerve function was evaluated by nerve conduction studies in all participants. The composite Z‐scores for nerve conduction parameters including conduction velocity (CV), amplitude and latency were calculated, respectively. RESULTS: Rs5219 of KCNJ11 (E23K, G→A) was identified to be associated with all the parameters obtained from nerve conduction studies (Z‐score of CV: β = 0.113, P = 0.01; Z‐score of amplitude: β = 0.133, P = 0.01; Z‐score of latency: β = −0.116, P = 0.01) after adjustment for covariates including age, duration and glycated hemoglobin. Specifically, each copy of the A allele was related to better outcomes. CDKAL1 rs7756992 and TCF7L2 rs7903146 correlated with the composite Z‐score of amplitude (P = 0.028 and P = 0.016, respectively), but not CV (P = 0.393 and P = 0.281, respectively) or latency (P = 0.286 and P = 0.273, respectively). There were no significant associations between the other seven SNPs and peripheral nerve function. CONCLUSIONS: Rs5219 at KCNJ11 (E23K) was associated with peripheral nerve function in a Chinese population with type 2 diabetes mellitus, suggesting shared genetic factors for type 2 diabetes mellitus and diabetic polyneuropathy in this population.