1个有汗性外胚层发育不良大家系的基因研究

目的 探讨有汗性外胚层发育不良 （HED）的临床特点和分子机制。方法 对1例HED先证者进行其家系5代91人的临床及基因特点研究。抽取家系中7名患者及3名正常对照进行GJB6基因检测。结果 家系5代91人中，HED患者17例，表现为不同程度的指 （趾）甲发育不良、毛发或体毛稀少甚至缺如；家系中男性患者毛发稀少程度重于女性；随着代数增加，指 （趾）甲损害渐减轻。系谱中每一代均有发病者，患者的父母中必有一人发病；男女都可患病；遗传方式为常染色体显性遗传。家系中所有患者的GJB6基因均存在一个杂合错义突变31G→A，家系中无HED临床表现的未检测到此突变。结论 HED为常染色体显性遗传性疾病，以指 （趾）甲发育不良、掌跖角化过度、毛发或体毛稀少甚至缺如为临床特点；男性毛发稀少重于女性；且随着代数的增加，指 （趾）甲损害逐渐减轻。GJB6基因错义突变 （31G→A）是HED的分子机制之一。

A gene study of a family with hidrotic ectodermal dysplasia

Objective To investigate the clinical features and molecular mechanism of hidrotic ectodermal dysplasia (HED). Methods A clinical and gene study was performed for ifve generations (91 people) in the family of one proband with HED. GJB6 gene detection was performed for 7 patients and 3 normal people in this family. Results Among the 91 people in this family, there were 17 HED patients, who were manifested as having dysplasia of the ifngernails and toenails and sparse or absent hair or body hair. The male patients had a greater degree of sparse hair compared with female patients. In the younger generations, damage to the ifngernails and toenails was gradually alleviated. There were patients in each generation, the patient’s mother or father deifnitely had this disease. Both males and females developed this disease, and the inheritance pattern was autosomal dominant inheritance. A heterozygous missense mutation, 31G→A, in GJB6 gene was detected in all patients in this family, but this mutation was not detected in family members without the clinical manifestations of HED. Conclusions HED is a hereditary disease with autosomal dominant inheritance and has the clinical features of dysplasia of the ifngernails and toenails, hyperkeratosis of palms and soles, and sparse or absent hair or body hair. Male patients have a greater degree of sparse hair. In the younger generations, damage to the ifngernails and toenails is gradually alleviated. The missense mutation 31G→A in the GJB6 gene may be one of the molecular mechanisms for HED.