Identification of genetic effects underlying type 2 diabetes in South Asian and European populations
Marie Loh, Weihua Zhang, Hong Kiat Ng, Katharina Schmid, Amel Lamri, Tong Lin, Meraj Ahmad, Jung‐Jin Lee, Maggie C. Y. Ng, Lauren E. Petty, Cassandra N. Spracklen, Fumihiko Takeuchi, Md. Tariqul Islam, Farzana Jasmine, Anuradhani Kasturiratne, Muhammad G. Kibriya, Karen L. Mohlke, Guillaume Paré, Gauri Prasad, Hasan Shahriar, Miao Ling Chee, H Janaka de Silva, James C. Engert, Hertzel C. Gerstein, K. Radha Mani, Charumathi Sabanayagam, Marijana Vujković, Rajitha Wickremasinghe, Tien Yin Wong, Chittaranjan S. Yajnik, Salim Yusuf, Habibul Ahsan, Dwaipayan Bharadwaj, Sonia S. Anand, Jennifer E. Below, Michael Boehnke, Donald W. Bowden, Giriraj R. Chandak, Ching‐Yu Cheng, Norihiro Kato, Anubha Mahajan, Xueling Sim, Mark I. McCarthy, Andrew P. Morris, Jaspal S. Kooner, Danish Saleheen, John C. Chambers
Abstract
Abstract South Asians are at high risk of developing type 2 diabetes (T2D). We carried out a genome-wide association meta-analysis with South Asian T2D cases ( n = 16,677) and controls ( n = 33,856), followed by combined analyses with Europeans (n eff = 231,420). We identify 21 novel genetic loci for significant association with T2D ( P = 4.7 × 10 −8 to 5.2 × 10 −12 ), to the best of our knowledge at the point of analysis. The loci are enriched for regulatory features, including DNA methylation and gene expression in relevant tissues, and highlight CHMP4B , PDHB , LRIG1 and other genes linked to adiposity and glucose metabolism. A polygenic risk score based on South Asian-derived summary statistics shows ~4-fold higher risk for T2D between the top and bottom quartile. Our results provide further insights into the genetic mechanisms underlying T2D, and highlight the opportunities for discovery from joint analysis of data from across ancestral populations.