一个先天性眼球震颤家系致病基因的初步定位

为确定一个X染色体显性遗传先天性眼球震颤家系的致病基因与X染色体的连锁关系， 选用X染色体上的DXS1214、DXS1068、DXS993、DXS8035、DXS1047、DXS8033、DXS1192和DXS1232共8个微卫星DNA标记对该家系进行基因扫描与基因分型，并利用LINKAGE等软件包对基因分型结果进行分析，探讨该家系致病基因与X染色体的连锁关系。 两点连锁分析时X染色体短臂4个基因座最大LOD值均小于-1，不支持与该家系致病基因连锁； X染色体长臂4个基因座中最大LOD值达到2，提示存在较大的连锁可能性。该家系的致病基因可初步定位于X染色体长臂，且提示Xq26-Xq28区间附近可能是先天性眼球震颤一个共同的致病基因座，但区间范围仍较大，仍须进一步选择合适的微卫星标记进行精确的定位以缩小候选基因的筛查范围。Abstract： To investigate the relationship between X chromosome and obligatory gene of a pedigree with congenital nystagmus，we used the following markers: DXS1214、DXS1068、DXS993、DXS8035、DXS1047、DXS8033、DXS1192 and DXS1232.Genome screening and genotyping were conducted in this pedigree of congenital nystagmus, and linkage analysis by LINKAGE package was used to determine the potential location. The linkage was not found on the Xp ( All LOD score <-1) but on Xq (the maximum LOD score=2). The related gene of this pedigree was located on the long arm of X chromosome. We demonstrate that Xq26-Xq28 is a common locus for CMN. It bring us closer to the identification of a gene responsible for X-linked CMN.

Mapping of a Pedigree with Congenital Nystagmus

To investigate the relationship between X chromosome and obligatory gene of a pedigree with congenital nystagmus,we used the following markers: DXS1214, DXS1068, DXS993, DXS8035, DXS1047, DXS8033, DXS1192 and DXS1232. Genome screening and genotyping were conducted in this pedigree of congenital nystagmus, and linkage analysis by LINKAGE package was used to determine the potential location. The linkage was not found on the Xp (All LOD score <-1) but on Xq (the maximum LOD score=2). The related gene of this pedigree was located on the long arm of X chromosome.We demonstrate that Xq26-Xq28 is a common locus for CMN. It bring us closer to the identification of a gene responsible for X-linked CMN.