遗传性对称性色素异常症两家系ADAR1基因新突变

Two novel mutations of the ADAR1 gene in two families with dyschromatosis symmetrica hereditaria

目的:检测遗传性对称性色素异常症(DSH)2个家系ADAR1基因的突变。方法:收集DSH 2个家系患者的外周血标本,采用PCR结合DNA直接测序的方法,检测了2个家系成员中共5例患者、5例表型正常者和50例无亲缘关系健康个体ADAR1基因突变情况。结果:家系Ⅰ中患者ADAR1基因12号外显子第3159位碱基G缺失,即c.3159delG,导致一新的移码突变p.L1053fs→1076X;家系Ⅱ中患者ADAR1基因13号外显子第3209位和第3210位碱基之间插入1个碱基C(c.3209insC),导致又一新的移码突变p.L1070fs→1092X,而在2个家系中正常人及50例无亲缘关系的健康个体均未发现相应突变。结论:2个家系DSH患者均存在ADAR1基因新的移码突变,可能由此引起编码蛋白的结构和功能的改变,致皮肤色素异常。

Objective ：To identify mutations of ADAR1 gene in two Chinese families with dyschromatosis symmetrica hereditaria. Method： Blood samples were collected from the patients and healthy members of two families. The whole coding region of ADAR1 gene was amplified by polymerase chain reaction （PCR） and PCR products were analyzed by direct sequencing. As control the DNA samples from 50 unrelated, normal adult individuals were also included. Results： A novel frame shift mutation, c.3159delG （p.L1053fs→1076X） ,of ADAR1 gene was detected in the patients of family I. Another novel frame shift mutation, c.3209insC（p. L1070fs→1092X）, was detected in patients of family Ⅱ. The mutations were not detected in unaffected family members and 50 normal control individuals. Conclusion： Two frame shift mutations in the ADAR1 gene have been detected in the two DSH families. These novel frame shift mutations may be the causes of the clinical phenotype in these two families.