摘要

Copy number variations (CNVs) have been implicated as an important genetic marker of common disease. In this study, we explored genetic effects of common CNVs in Type 2 diabetes (T2D) related susceptible genes in Chinese population. @@@ Seven common CNV loci were selected from genes enclosing the susceptible single nucleotide polymorphisms (SNPs) of T2D confirmed by genome-wide association studies (GWAS) and replication studies conducted in east Asia population. The CNVs and SNPs were genotyped in 504 T2D patients and 494 non-T2D controls. Cumulative effect of the positive CNV loci was measured using genetic risk score (GRS). Multiplicative and additive interaction between candidate CNV loci and SNPs were assessed. @@@ Compared with the common two copies, the deletion of nsv6360 (adjusted OR = 2.28, 95% CI 1.37-3.78, P = 0.001), nsv8414 (adjusted OR = 1.89, 95% CI 1.16-3.08, P = 0.006) and nsv1898 (adjusted OR = 1.84, 95% CI 1.19-2.84, P = 0.005) were significantly associated with increased risk of T2D (P < 0.007). Significant dose-response relationship was observed between GRS and the risk of T2D (chi (2) for trend = 19.51, P < 0.001). In addition, significant additive interactions between nsv8414 and rs17584499 in PTPRD (AP = 0.60, 95% CI 0.12-1.07) and nsv1898 and rs16955379 in CMIP (AP = 0.46, 95% CI 0.01-0.91) were observed. @@@ There were three CNV loci (nsv6360, nsv8414 and nsv1898) associated with T2D, and a significant cumulative effect of these loci on the risk of T2D. The comprehensive effects of both CNVs and SNPs may provide a more useful tool for the identification of genetic susceptibility for T2D.