The results of a worldwide study on diabetes in which Hyderabad-based CSIR – Centre for Cellular and Molecular Biology (CSIR-CCMB) was involved, paves the way towards development of ancestry-specific genetic risk score for risk prediction in different populations and has immense implications for Indians, where every sixth individual is a potential diabetic, the CCMB said Thursday.
The study of diverse populations has shed a new light on how genes contribute to Type-2 Diabetes. The study named DIAMANTE (DIAbetes Meta-Analysis of Trans-Ethnic association studies) co-led by Prof Andrew Morris at the University of Manchester is now published in Nature Genetics, CCMB said.
Dr Giriraj R Chandak, Chief Scientist at CCMB and one of the lead investigators from India, highlighted this study as a landmark event where scientists from different parts of the world put together their minds to understand similarities and differences in genetic susceptibility to Type-2 Diabetes in different populations. Dr Chandak’s group had earlier provided evidence of greater genetic heterogeneity in Indians compared to Europeans, which compromises our ability to predict Type 2 Diabetes risk in the Indian populations using European data.
The global prevalence of Type 2 Diabetes, a familial disease with severe morbidity, has increased 4-fold over the last three decades. South Asia, especially India and China, are major hubs of this spurt. It is thought that Indians are especially at risk of Type-2 Diabetes because they are centrally obese meaning fat around the abdomen – indicative of fat around their visceral organs and are more insulin resistant right from birth.
This is in contrast to the Europeans who are overall fat in a generalised manner. Despite this fact, the largest studies to understand the genetic basis of Type-2 Diabetes have mostly been conducted on populations of European ancestry.
This recent study compared genomic DNA of 1.8 lakh people with Type-2 Diabetes against 11.6 lakh normal subjects from five ancestries – Europeans, East Asians, South Asians, Africans and Hispanics — and identified large number of genetic differences (Single Nucleotide Polymorphisms or SNPs) between patients and the normal subjects. “The study found population-specific differences in genetic susceptibility to Type-2 Diabetes. These results pave the way towards development of ancestry-specific genetic risk scores for risk prediction in different populations and have immense implications for Indians, where every sixth individual is a potential diabetic,” said Dr Chandak.
“This study sets up the stage for further investigating the South Asian population for genetic susceptibility to Type-2 Diabetes and extends the journey on the path of precision medicine,” said Dr Vinay Nandicoori, Director, CCMB.