Dennehy P J, Feldman G L, Kambouris M, O'Malley E R, Sanders C Y, Jackson C E
Department of Ophthalmology, Henry Ford Health Science Center, Detroit, Michigan, USA.
Am J Ophthalmol. 1995 Oct;120(4):456-61. doi: 10.1016/s0002-9394(14)72659-5.
We studied a two-generation family with an inherited syndrome of prominent corneal nerves and lesions of the tongue resembling neuromas without the characteristic neoplasms of the multiple endocrine neoplasia type 2B syndrome. Several different point mutations in the RET proto-oncogene on chromosome 10 have been associated with the multiple endocrine neoplasia type 2 syndromes. Molecular genetic studies of families with partial phenotypic expression of these syndromes may aid in further understanding the origin of the variety of clinical manifestations observed in multiple endocrine neoplasia type 2.
A family consisting of an 8-year-old male proband, his 10-year-old sister, and 40-year-old mother was identified as having prominent corneal nerves and lesions of the tongue resembling neuromas. Pentagastrin-stimulated serum calcitonin levels were measured in the mother and sister. Molecular genetic studies were performed on all three affected members, to look for the specific point mutation seen in over 95% of patients with multiple endocrine neoplasia type 2B.
Serum calcitonin levels were normal, indicating no C-cell hyperplasia or medullary thyroid carcinoma. Molecular genetic studies on these individuals did not disclose the specific point mutation seen in multiple endocrine neoplasia type 2B.
This family demonstrates some of the phenotypic features of the multiple endocrine neoplasia type 2B syndrome without the characteristic neoplasms or the mutation in the RET proto-oncogene associated with multiple endocrine neoplasia type 2B. Their physical findings may be caused by genetic alterations within the RET proto-oncogene on chromosome 10 at yet undetermined sites.
我们研究了一个两代家族，该家族患有遗传性角膜神经突出综合征以及类似神经瘤的舌部病变，但无2B型多发性内分泌肿瘤综合征的特征性肿瘤。10号染色体上RET原癌基因的几种不同点突变与2型多发性内分泌肿瘤综合征相关。对这些综合征部分表型表达的家族进行分子遗传学研究，可能有助于进一步了解2型多发性内分泌肿瘤中观察到的各种临床表现的起源。
一个由8岁男性先证者、他10岁的姐姐和40岁的母亲组成的家族被确定患有角膜神经突出和类似神经瘤的舌部病变。对母亲和姐姐进行了五肽胃泌素刺激后的血清降钙素水平测定。对所有三名受影响成员进行了分子遗传学研究，以寻找在超过95%的2B型多发性内分泌肿瘤患者中出现的特定点突变。
血清降钙素水平正常，表明无C细胞增生或甲状腺髓样癌。对这些个体的分子遗传学研究未发现2B型多发性内分泌肿瘤中出现的特定点突变。
该家族表现出2B型多发性内分泌肿瘤综合征的一些表型特征，但无特征性肿瘤或与2B型多发性内分泌肿瘤相关的RET原癌基因突变。他们的体格检查结果可能是由10号染色体上RET原癌基因尚未确定位点的基因改变引起的。
