KCNJ11 activating mutation in an Indian family with remitting and relapsing diabetes

Abstract

To identify the genetic cause of transient neonatal diabetes mellitus in three siblings from an Indian family. Case reports with clinical and molecular evaluation of an activating mutation in the KCNJ11 gene are presented. We describe an Indian family with two asymptomatic parents with 3 children presenting with hyperglycemia at 6, 1.5 and 1 month of age respectively. Blood glucose levels at presentation were 22.2, 18.3 and 20 mmol/L and the diabetes remitted in all three children by 5 years of age. None of the affected siblings had dysmorphism or neurological abnormalities. Diabetes relapsed in the oldest sibling at 9.4 years of age and she is now euglycemic on 1mg/Kg of Glibenclamide twice a day. A novel heterozygous missense mutation (G53V) in the KCNJ11 gene was identified in all 3 affected children and the father. Our report suggests that screening for KCNJ11 mutations is appropriate in patients diagnosed with neonatal diabetes as it provides valuable information concerning possible course of the disease and choice of treatment.