A group of Taiwan scientists recently successfully identified two genes that are associated with type 2 diabetes in Han Chinese. Their research was published in the February 19 issue of the international scientific journal PLoS Genetics.

Type 2 diabetes is a chronic metabolic disorder caused by inadequate response to insulin by the body. Both environmental factors, such as diet and exercise, and genetic factors affect the age of disease onset and symptom progress. Type 2 diabetes currently affects approximately 360 million people or about 6% of the world population; by 2025 this figure is expected to rise to around 25%.

For this study researchers analyzed the genes of 2798 patients with type 2 diabetes using high density genotyping technology. They identified two genes named protein tyrosin phosphatase receptor (PTPRD) and serine racemase (SRR) that were associated with type 2 diabetes in ethnic Han Chinese. Variation in PTPRD may affect the body’s resistance to insulin, and therefore influence the body’s blood glucose metabolism. SRR gene variation may alter glutamate signaling in the pancreas, thus regulating insulin and/or glucagon secretion. The study also confirmed that the KCNQ1 gene, which was previously identified in a study of type 2 diabetes in Japanese, also plays an important role in the pathogenesis of type 2 diabetes in Han Chinese.

The study was the result of collaboration between researchers at the China Medical University, the Institute of Biomedical Sciences at Academia Sinica, National Taiwan University College of Medicine, and the Chia-Yi Christian Hospital.

Dr. Fuu-Jen Tsai of China Medical University who led the research said that this study marks important progress in the identification of disease genes for type 2 diabetes in Han Chinese. Many severe complications are caused by type 2 diabetes, including cataract, glaucoma, kidney failure, coronary heart disease, retina damage, neuropathy, stoke, peripheral arterial disease and gangrene. Dr. Tsai said that with the combined efforts of public health and medical centers, he hopes that in the future genetic factors associated with these complications can also be identified, leading to advances in medical care, therapy and prevention.

Dr. Jer-Yuarn Wu, Director of the National Genotyping Center and the research project’s co-principal investigator who led the genotyping work said that the study successfully establishes a genetic database for type 2 diabetes in Han Chinese residing in Taiwan and conclusively identifies disease genes specific for Han Chinese.

Dr. Yuan-Tsong Chen, Director of the Institute of Biomedical Science at Academia Sinica said that one of the major contributions of the research is to show that different disease genes exist for the same disorders in different populations.

The findings from this study could help scientists understand more about the disease progress of type 2 diabetes as well as design and develop new drugs for type 2 diabetes.

The full article entitled “A Genome-Wide Association Study Identifies Susceptibility Variants for Type 2 Diabetes in Han Chinese” is available at the PLoS journal website at: http://www.plosgenetics.org/home.action

The full list of authors is: Fuu-Jen Tsai, Chi-Fan Yang, Ching-Chu Chen, Lee-Ming Chuang, Chieh-Hsiang Lu, Chwen-Tzuei Chang, Tzu-Yuan Wang, Rong-Hsing Chen, Chiung-Fang Shiu, Yi-Min Liu, Chih-Chun Chang, Pei Chen, Chien-Hsiun Chen, Cathy S. J. Fann, Yuan-Tsong Chen and Jer-Yuarn Wu.

PLoS Genetics is an open-access, peer-reviewed journal published weekly by The Public Library of Science, a nonprofit organization. Other publications issued by the US-based publisher include PLoS Biology, PLoS Medicine and PLoS Computational Biology.