The gene is a neuro gene with no known association with Diabetes

The discovery of a new gene causing Type 2 diabetes in the Indian population by an entirely Indian cast of researchers has opened up a hitherto unknown and new line of enquiry into the mechanism of the disease.

According to a paper published in the December edition of Diabetes, the gene was identified after running through a massive sample size of over 12,500 persons in the Indian subcontinent. “The new gene that was identified is a neuro gene, with no known association with Diabetes. So what is it doing in Type 2 Diabetes?” the principal investigator of the study, Dwaipayan Bharadwaj, said. He is with the Genomics and Molecular Medicine Unit, Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology, Delhi.

“Among the common variants, this is the major variant in the Indian population. So it certainly has a role to play. My hypothesis is, perhaps, diabetes is more a neurological disorder – it probably explains the temptation to eat when you see a plate of good food in front of you,” Dr. Bharadwaj added. This gene increases the risk of developing Type 2 Diabetes to 1.6 times higher in the Indian population.

The involvement of a neuro gene opens up a spectacularly new area, said Nikhil Tandon, one of the authors, who is a professor of Endocrinology at AIIMS. It facilitates a potentially new line of enquiry into understanding of the mechanism of this disease. “This gene is a synaptic transporter. Maybe there is an issue with the way insulin is being transported? Various functional studies have been lined up down the road,” he said. Understanding the mechanism will translate to better diagnostics and treatment methods, though that is still in the distant future, he added.

The association of this gene with diabetes in the Indian population is higher and stronger than any other gene, the authors explain.

The other key point in this study, Dr. Bharadwaj explains, is that it is entirely Indian with a massive sample size. The two groups that were studied included North Indians, and Dravidians, the latter sample provided from the Chennai-based Madras Diabetes Research Foundation – Indian Council for Medical Research Advanced Centre for Genomics of Diabetes.

Dr. Tandon said, “If you look at all collaborative research in genetics, most of them are initiated and driven by developed country partners. Even if there are Indians, they are possibly one of a large body of investigators. It is an important point that a study of this magnitude has been conceived in India, funded by Indian money (CSIR), and was completely executed by Indians.”

Bringing to play all the 60 known genes causing diabetes still explains only about 10 per cent of the risk of diabetes, Dr. Bharadwaj says. There is a huge role for environmental and lifestyle risk factors on the disease. Dr. Tandon added, “It does mean that even if you have bad genes, you can sort yourself out.”