Identification of the disease gene of dyschromatosis symmetrica hereditaria.

遗传性色素异常症（DSH）是一种常染色体显性遗传性色素异常症，由富山于1910年首次报道。它的特征是手和足背上各种大小的色素减退和色素沉着过度的混合斑。DSH的病因、发病机制、致病基因及其染色体定位尚未明确。因此，我们提出了在三个日本DSH家族中进行DSH基因和每条染色体上的微卫星标记之间的连锁分析的项目我们获得了3个LOD值大于5的微卫星标记，并在单核苷酸多态性（SNP）分析后将候选基因的位置缩小到3Mb左右分析.我们现在试图在3Mb染色体区域识别的几个有希望的基因中找到任何突变。

Dyschromatosis symmetrica hereditaria (DSH) is an autosomal dominant pigmentary disorder, first reported by Toyama in 1910. It is characterized by a mixture of hypopigmented and hyperpigmented macules of various sizes on the backs of the hands and feet. The cause and the pathogenesis as well as the disease gene of DSH and its chromosomal localization have not yet been clarified. Thus we made the project performing linkage analysis between the DSH gene and microsatellite markers on each chromosome in three Japanese DSH families (83 patients in total) in order to finally identify the DSH gene.We obtained three microsatellite markers showing high log ratio of odds (LOD) score more than 5 and then narrowed the location of the candidate gene to about 3 Mb after the single nucleotide polymorphism (SNP) analysis. We now try to find any mutation (s) in several hopeful genes recognized in the 3Mb chromosomal region.