Namihira H, Sato M, Miyauchi A, Ohye H, Matsubara S, Bhuiyan M M, Murao K, Ameno S, Ameno K, Ijiri I, Takahara J
First Department of Internal Medicine, Kagawa Medical University, , Kita-gun, Japan.
Endocr J. 2000 Feb;47(1):37-43. doi: 10.1507/endocrj.47.37.
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 (569del1, 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. In two generations of this family, eight of eleven family members had PHP and four of them were found to have other MEN1-related lesions. Both of the monozygotic twins had PHP. Interestingly, one had pancreatic tumor but the other had no evidence of it. Pituitary MRI showed no pituitary lesion in either of them. This is the first Japanese case of monozygotic twins with different MEN1 phenotypes.
我们报告了一对表现出不同MEN1表型的单卵双胞胎。先证者（28岁，女性）患有原发性甲状旁腺功能亢进症（PHP）和胰岛素瘤，基因分析显示MEN1基因存在一个点突变（569del1，第3外显子）。该突变导致移码，并在第184密码子处产生一个终止密码子。限制性酶切（HinfI）分析证实，包括她的两个姐妹（这对单卵双胞胎）在内的6名受影响成员中存在相同的MEN1基因突变，而两名未受影响成员中未发现此类突变。在这个家族的两代人中，11名家族成员中有8人患有PHP，其中4人被发现患有其他与MEN1相关的病变。这对单卵双胞胎都患有PHP。有趣的是，其中一人有胰腺肿瘤，而另一人没有。垂体MRI显示他们两人均无垂体病变。这是日本首例具有不同MEN1表型的单卵双胞胎病例。
