【摘要】 目的 检测16个家系20例性连锁Alport综合征患者COL4A5基因突变。方法 采用PCR-变性凝胶梯度电泳(DGGE)-直接测序法检测患者COL4A5基因中30个外显子及其相邻内含子区域(外显子1～25、31、32、41、50、51),另选取100例正常人外周血DNA作为对照。结果 共发现4种突变,包括1种位于1号外显子上的无义突变(266C→T谷氨酰胺22终止密码),1种位于31号外显子上的错义突变(2757G→T甘氨酸852缬氨酸),以及2种分别位于1、25号内含子区域的剪接突变(283+1G→T、2150+1G→T)。结论 COL4A5基因为性连锁Alport综合征的致病基因,突变类型多样,尚未发现热点突变。类似于外显子突变,内含子突变同样具有致病意义,患者临床症状典型。查阅基因库,此4种突变均为首次报道。更多还原

【Abstract】 Objective To screen the mutations in 30 exons of COL4A5 gene from X-linked Alport syndrome. Methods 20 Chinese X-linked Alport syndrome patients from 16 families were examined. Genomic DNA was extracted from peripheral leukocyte and exon-specific primers were designed for 30 exons(1-25、31、 32、41、 50、51) . Polymerase chain reaction amplification was performed and followed bydegenerating gel gradient electrophoresis (DGGE) analysis. All abnormal migration bands were sequenced and one hundred normal persons selected as control. Results Four abnormal bands were detected, which were all point mutations and predicted to be functionally pathogenic, in four unrelated patients. One patienthad a nonsense mutation in exon 1 (Glu 22 Term); one had a missense mutation in exon 3l(Gly852Val).Two patients carried splicing mutations in intron 1 and 25 respectively(283+1G→T、2150 + 1G→T) .Conclusions X-linked Alport syndrome is caused by various kinds of COL4A5 gene mutations without any hotspot. Paralleled with the significance of exon mutations, intron mutations also play a critical role in the pathogenesis. Furthermore, these four pathogenic mutations have never been reported in the genebank and showed good correlation with clinical manifestations.更多还原