Which genetic mutation is primarily associated with congenital hyperinsulinism leading to severe hypoglycemia in infants?

The ABCC8 gene mutation is primarily associated with congenital hyperinsulinism, which leads to severe hypoglycemia in infants. The ABCC8 gene encodes for a subunit of the ATP-sensitive potassium channel in the pancreatic beta cells. Mutations in this gene disrupt the normal functioning of these channels, causing inappropriate insulin secretion even in the presence of low blood sugar levels. This unregulated release of insulin leads to hypoglycemia, a hallmark of congenital hyperinsulinism.

Newborns or infants with this condition often present with severe hypoglycemic episodes shortly after birth, which can be life-threatening if not managed properly. Early diagnosis and treatment are crucial to prevent potential neurological damage and ensure proper glucose levels are maintained.

Other genetic mutations listed, such as those in the INS gene, GCK gene, and HNF4A gene, are associated with different forms of diabetes or altered insulin secretion but are not primarily linked with congenital hyperinsulinism in the same way that ABCC8 mutations are.