HYPERINSULINISM - MOLECULAR ETIOLOGY OF FOCAL DISEASE

Persistent hypoglycaemia in infancy is most commonly caused by hyperin sulinism. A case is reported of the somatic loss of the maternal 11p i n an insulin secreting focal adenoma in association with a germline SU R-1 mutation on the paternal allele in a baby boy with hyperinsulinism diagnosed at 49 days old. A reduction to homozygosity of an SUR-1 mut ation is proposed as a critical part of the cause of focal hyperinsuli nism.