Harvard researchers, including one of Indian-origin, have identified nine genetic variants that dramatically increase the risk of developing type 2 diabetes.
Amit Majithia, instructor in medicine at Harvard Medical School (HMS) and at Harvard-affiliated Massachusetts General Hospital said the variants increase the risk of developing type 2 diabetes sevenfold, but are very rare in the population, found in just one in 1,000 individuals.
Researchers studied PPARG gene which has been known to be associated with diabetes risk for 20 years.
They scanned the genomes of 20,000 people from various international populations and found 53 mutations, only four of which had been previously described.
Further experimentation showed that nine of the 49 remaining mutations caused changes in key proteins that increased the risk of type 2 diabetes, 'Harvard Gazette' reported.
"These rare mutations are only seen in one in 1,000 individuals, but the effect on the individual is very strong because they increase risk by 700 per cent," Majithia said.
The PPARG gene, which regulates the development of fat cells, encodes a protein made up of 500 amino acids.
With 19 possible amino acids that could be plugged in at each position, there are nearly 10,000 possible mutations, Majithia said, making it highly likely that there are additional mutations - possibly many of them - that affect diabetes risk.
The work was published in the Proceedings of the National Academy of Sciences.