摘要目的 探讨中国汉族斑驳病一家系的临床特征和基因突变情况.方法 对该家系临床资料进行收集、整理、照相存档及临床遗传学特征分析,并绘制系谱图.提取家系成员和正常人对照者外周血基因组DNA,采用PCR及DNA直接测序的方法对该家系进行基因突变检测.结果 该家系成员共73人.根据典型的临床特征,先证者及其他患者共14例均确诊为斑驳病,遗传方式为常染色体显性遗传.家系中患者均存在KIT基因13号外显子第1900位ATGA插入(1900insATGA),导致第634位密码子处出现移码突变,KIT蛋白多肽翻译提前终止于第641位密码子.家系其他成员及50例正常人对照者未发现此突变.该突变位点此前未见报道.结论 一种新的KIT基因突变(1900insATGA)可能是引起该斑驳病家系临床表型的原因.

abstractsObjective To investigate the clinical features of and gene mutations in a Chinese Han pedigree with piebaldism. Methods Clinical data were collected with informed consent from a pedigree with piebaldism, processed and documented. A clinical genetic analysis was conducted and pedigree chart was drawn. Genomic DNA was extracted from the peripheral blood of 14 patients and 40 unaffected individuals in the family as well as 50 unrelated human controls, and subjected to the amplification of 21 exons and flanking sequences of the KIT gene by PCR. Sequence analysis was performed by Mutation SurveyorTM. Results There were 73 members in the family, and of them, 14 were diagnosed with piebaldism according to typical clinical features. Piebaldism was inherited in an autosomal dominant pattern in this family. A heterozygous 4-base insertion mutation 1900insATGA in exon 13 of KIT gene was identified in all the 14 affected family members, which resulted in a frame-shift mutation at codon 634 and produced a premature translation termination codon. This mutation was undetected in either the unaffected family members or unrelated controls. Up to the time of this writing, this mutation had not been previously reported. Conclusion The novel mutation 1900insATGA in the KIT gene may be the cause of clinical phenotype of piebaldism in the family.