New genes for diabetes in South Asians found


Scientists have reported six new genes linked to a common form of diabetes among South Asians.

The genes turned up in a six-country ‘Genome Wide Association Study’ (GWAS) —  looking at variations in genes among individuals of a specific population — covering 58,587 South Asians based in India, Mauritius, Pakistan, Singapore, and Sri Lanka.

A report of the study, published in Nature Genetics last month (28 August), said South Asians had fourfold higher risk of developing ‘Type 2 diabetes’, marked by high sugar (glucose) levels in blood.

This form of diabetes — which affects some 55 million South Asians and is projected to affect 80 million by 2030 — results from incorrect response to the insulin hormone that moves sugars from blood to fat, liver and muscles where they are stored for energy.

Viswanathan Mohan, founder of the Madras Diabetes Research Foundation (MDRF), Chennai, and chief diabetologist at the Indian Council for Medical Research’s Advanced Centre for Genomics of Diabetes, also in Chennai, told SciDev.Net that the identification of the six new genes will “perhaps lead to future therapies for diabetes.”

Mohan, who was part of the GWAS team, said scientists did not previously know that five of the six genes were linked to diabetes.

Scientists worldwide have so far identified 42 genes linked with diabetes among European populations and these would need further study for their specific contribution to the ailment, Mohan explained.

Mohan said that it may take “several years of follow-up and cutting-edge research to find application in society.” Until then, simple methods such as a test to assess diabetes risk could help doctors make timely interventions.

Mohan’s team at MDRF has developed a simple technique, the Indian Diabetes Risk Score, which assesses genetic susceptibility such as family history of diabetes and other factors like physical inactivity and waist measurement to identify individuals at risk for diabetes. (Papri Sri Raman/SciDev)