1129-P: The Genetic Architecture of Cardiovascular Disease in Individuals with Type 2 Diabetes

Abstract

Background: Type 2 diabetes mellitus (T2DM) is a known risk factor for cardiovascular disease including coronary heart disease (CHD), stroke, and peripheral vascular disease (PVD). However, the genetic underpinnings of cardiovascular disease in those with T2DM is not well understood. Methods: Using 15 studies from dbGaP and the UK Biobank, we conducted the largest to date genome-wide association studies (GWAS) for CHD, stroke and PVD in up to 61,880 individuals with T2DM including 47,140 of European, 8,891 of African, 2,622 of Hispanic, 2,120 of South Asian and 1,107 of East Asian ancestry. GWAS were combined via ancestry-specific and transethnic meta-analyses with fixed-effects. Additional transethnic analysis with MR-MEGA was conducted to account for heterogeneity in allelic effects correlated with ancestry. Results: We replicated previously reported CHD associated loci at genome-wide significance (GW, p≤5×10-8) including 9p21, LPA, and PSRC1. Combining our results with those of prior CHD GWAS in T2DM revealed additional GW significant signals in known CHD loci: PHACTR1, ADAMTS7, HHIPL1, and LPL. European ancestry specific analysis confirmed prior GW significant associations between LPA and PHACTR1 loci and PVD. MR-MEGA analysis of PVD identified novel GW significant loci in CNST and AVPI1. We found a significant genetic correlation of 0.74 (SE= .27) between CHD and PVD. Transethnic analysis of stroke GWAS yielded no GW significant loci. However, African ancestry specific analysis yielded two novel GW signals in the NKAIN2 and BRF1 loci. A significant association between interleukin-6 signaling and stroke was identified using pathway analysis. Conclusions: Ancestry-specific and transethnic analysis of cardiovascular disease in T2DM confirmed prior CHD GWAS findings and revealed novel associations with PVD and stroke that warrant further investigation. Disclosure E. L. Richard: None. S. Cao: None. A. Shadyab: None. R. Salem: None. Funding National Institutes of Health