一个遗传性全白甲中国家系FZD5、LOC729607基因突变分析

FZD5,LOC729607 gene mutation analysis in a Chinese pedigree with hereditary leukonychia totalis

背景:遗传性全白甲是一种少见的常染色体显性遗传病,其致病基因目前尚未发现。目的:对一个中国汉族遗传性全白甲家系的2个候选基因进行突变筛查检测,研究遗传性全白甲的分子遗传基础。设计、时间及地点:候选基因突变筛查检测,于2007-01/06在中国人类基因组北方研究中心实验室完成。材料:搜集一遗传性全白甲家系患者静脉血,制备基因组DNA。方法:采用定位候选克隆法,在已经定位的致病基因区域内,选择FZD5,LOC729607基因进行突变筛查。应用PCR扩增、PCR产物直接测序的方法检测和对比遗传性全白甲家系内3例患者和一个正常人候选基因的外显子区及邻近内含子区域碱基顺序,并将测序结果与NCBI数据库内标准系列对比。主要观察指标:检测和对比遗传性全白甲家系内患者和正常人候选基因的外显子区及邻近内含子区域碱基顺序,并将测序结果与NCBI数据库内标准系列对比,发现患者、正常人、标准系列碱基顺序的差异,分析这些差异的意义。结果:FZD5基因exon706位碱基A→G;LOC729607基因exon5下游51661位缺T,exon6上游57257位C→T,exon7上游71187位AG杂合。所检测到的变异在家系中患者和正常人中都存在,在NCBI数据库中能查到相应的位点,是单核苷酸多态。结论:在FZD5(frizzled5),LOC729607基因编码区域及邻近非编码区域中未发现遗传性全白甲家系的致病突变。

BACKGROUND： Hereditary leukonychia totalis is a rare genealogy of autosomal dominant inheritance disease, which pathogenic gene remains unclear. OBJECTIVE： To analyze FZD5, LOC729607 gene mutation in a Chinese pedigree with autosomal dominant hereditary leukonychia totalis, and to explore the molecular genetics basis for hereditary leukonychia totalis. DESIGN, TIME AND SETTING： The candidate gene mutation detection was performed in the Chinese National Human Genome Center from January to June, 2007. MATERIALS： Venous blood of patients with pedigree leukonychia totalis were collected and prepared for genome DNA. METHODS： Mutation screening of FZD5, LOC729607 gene in patients with leukonychia totalis were underwent in the region of virulence gene which located by positional candidate cloning. Detected and contrasted RNA base sequence between 3 patients and health adult by means of polymerase chain reaction and direct sequencing, then compared the sequencing results with standard series supplied by NCBI, MAIN OUTCOME MEASURES： Detected and compared the base sequence of candidate gene in exon and intron region, analyzed the singnificances among patients, health adult and standard series compared the direct sequencing result with standard sequence of FZD5, LOC729607 genes in NCBI. RESULTS： Four mutations were found in all exons and their flanking intronic sequences of the two genes. Namely 706 A→G in FZD5, 51661 absence ofT, 57257 C→T and 71187 AG heterozygosis in LOC729607. The mutation could also be found in heath adult and checked by NCBI, which was polymorphism of single nucleotide. CONCLUSION： The pathogenic mutation of hereditary leukonychia totalis can not be found in exons and their flanking intronic sequences in FZD5 （frizzled 5） and LOC729607.