Different Phenotypes of Multiple Endocrine Neoplasia Type 1 (MEN1) in Monozygotic Twins Found in a Japanese MEN1 Family with MEN1 Gene Mutation

摘要

We report monozygotic twins who showed different MEN1 phenotypes. The proband (28 y. O., female) had both primary hyperparathyroidism (PHP) and insulinoma, and genetic analysis revealed a point mutation (569dell, exon 3) of the MEN1 gene. This mutation causes a frameshift and produces a stop codon at codon 184. Restriction digestion (HinfI) analysis confirmed the same mutation of the MEN1 gene in six of the affected members Including her two sisters, the monozygotic twins, and no such mutation in two unaffected members.