Somewhere inside Kamalavalli, unbeknownst to any, lurked a single gene, a mutant. It took all of three months for anyone to discover this rogue gene, and when they did, the infant had a blood sugar count of 1200 mg/dL.

At three months after birth, Kamalavalli had constant fever, swelling and mild shaking of her left hand. Her parents, Gokulakrishnan and Revathy, were desperate to find out what was wrong with their first-born. When paediatricians finally figured out the problem, it came as a huge shock to the couple – their baby had neonataldiabetes mellitus (NDM). “Diabetes at three-months? Even as we were distressed, we tried to understand what that meant,” says Mr. Gokulakrishnan, a contractor from Thanjavur.

NDM is a rare form of diabetes that is diagnosed before six months of age, and is caused due to a single gene defect. The genetic disorder affects the pancreas' ability to secrete insulin, explains V.Mohan, chairman and chief diabetologist, Dr. Mohan's Diabetes Specialties Centre (DMDSC). The common forms of diabetes, Types 1 and 2, are supposed to be polygenic, he adds, indicating the involvement of multiple genes. Since environmental factors, including obesity, play a big role in the development of Type 2, getting a hold on such factors can help prevent and control the progression of diabetes.

In Kamalavalli's instance, her parents were found to be carriers of the gene mutation, though non-diabetic. Diabetologists have put her on 14 units of insulin a day, and since she was three months old, Kamalavalli has been getting injections twice a day.