【摘要】 目的研究念珠状发一家系基因突变情况及与表现型的关系。方法光镜下观察毛干结构,应用聚合酶链反应(PCR)和DNA直接测序技术检测基因突变位置和突变方式。结果光镜下患者的毛干呈粗细不均的梭形,似珍珠项链。家系中患者人毛发角蛋白6(hHb6)基因的第1 204位碱基鸟嘌呤(G)被腺嘌呤(A)替代,导致第7外显子出现E402K错义突变。家系中健康者和正常对照均未发现此突变。结论hHb6的E402K突变是该家系中患病成员发病的分子基础,念珠状发的基因型与表现型的不一致性,可能由基因突变及其他因素共同造成。更多还原

【Abstract】 Objective To investigate the gene mutation in a pedigree with monilethrix and the correlation between the genotype and phenotype of monilethrix.Methods Light microscopy was used to observe the structure of hair shafts;PCR and direct DNA sequencing were employed to determine the muta- tion sites and modes.Results The hair shafts showed a regular periodicity of nodes and narrow intemodes, like a pearl necklace.A heterozygous transition mutation of G→A at position 1204 in exon 7 ofhHb6 gene was determined in the affected relatives of the pedigree,but not found in his healthy relatives or 50 unrelated individuals.Conclusions The E402K mutation of hHb6 gene may be pathogenic for this case of monilethrix.The gene mutation,likely with other cofactors,may cause the phenotypic variation of monilethrix.更多还原