Identification of Two New Mutations in the Glucokinase Gene That Result in Maturity-Onset Diabetes of the Young

Glucokinase catalyzes glucose to glucose-6-phosphate conversion in the pancreatic β-cell and is a key regulator of insulin secretion (1). The glucokinase gene ( GCK ) on chromosome 7p15.3–15.1 has 12 exons. GCK heterozygous inactivating mutations result in mild fasting hyperglycemia termed maturity-onset diabetes of the young type 2 (MODY2) or MODY-GCK (MIM # 125851) (2). The mutations result in diminished insulin secretion (3) and possibly decreased hepatic glucose uptake and glycogen synthesis (4). Several hundred inactivating mutations throughout exons 2 to 10 have been described (5). We report two previously undescribed mutations.Both patients were assessed at the Pediatric Diabetes Education Centre, Stollery Children's Hospital, Edmonton, Canada. Glucose and A1C …