【摘要】 目的　检测中国人Ａｌｐｏｒｔ 综合征（ＡＳ） 患者编码Ⅳ型胶原α５ 链的ＣＯＬ４Ａ５ 基因突变。方法　提取１８ 例中国Ｘ连锁显性遗传型ＡＳ患者基因组ＤＮＡ，据ＣＯＬ４Ａ５ 基因中与外显子相邻的内含子序列设计引物，分别作ＤＮＡ聚合酶链式反应（ＰＣＲ） ，扩增了该基因第２０～５１ 外显子。以琼脂糖凝胶电泳鉴定产物，作单链构象多态性（ＳＳＣＰ） 分析检测ＰＣＲ 产物，对迁移率异常者进行ＤＮＡ 测序。结果　ＰＣＲＳＳＣＰ分析发现患者８ 的２０、３９ 和４６ 外显子，以及患者９０ 的２６ 外显子的ＰＣＲ 产物单链ＤＮＡ迁移率异常，亦发现患者８ 之母存在与其相同的异常迁移带以及正常迁移带。ＤＮＡ 测序证实患者８ 的ＣＯＬ４Ａ５ 基因第２０ 外显子１１５７ 和１１５８ 位缺失ＣＣ两个碱基，而第３９ 及４６ 外显子为同义突变；患者９０ 第２６ 外显子２１７１ 位缺失一个Ｃ碱基。这两位患者的缺失突变均致移码突变，并使终止密码子提前出现，导致Ⅳ型胶原α５ 链显著缩短。结论　首次报道了中国大陆ＡＳ患者ＣＯＬ４Ａ５ 基因的两个小缺失突变，其中一个缺失突变伴有两个同义突变，未发现大片段缺失及重组突变。通过ＰＣＲＳＳＣＰ分析亦证实一患者之母为ＣＯＬ４Ａ５ 基因的?更多还原

【Abstract】 Objective To detect mutations in COL4A5 gene encoding type Ⅳ collagen α 5 chain in Chinese AS patients Methods Genomic DNA from 18 unrelated patients (12 males and 6 females) with X linked AS were analyzed So far, 32 of 51 exons at the 3′ end portion of COL4A5 gene were amplified with the primers synthesized according to the published flanking intronic sequences The PCR products were further analyzed by agarose gel electrophoresis and single strand conformation polymorphism (SSCP) analysis The PCR products showing polymorphism by SSCP analysis were directly sequenced Results By PCR SSCP analysis, 4 PCR products were identified with different mobility of single strand DNA, exon 20, 39 and 46 in patient No 8; exon 26 in patient No 90 The PCR product of No 8 patient′s mother was revealed with a special pattern containing single strand DNA bands identical to those of the No 8 patient and the normal control DNA sequencing analyses revealed: (1) silent mutations in exon 46 and 39; (2) exon 20 was deleted with CC nucleotides and exon 26 was deleted with one C nucleotide , both of which induced nonsense mutations resulting in remarkably truncated α 5 chains of type Ⅳ collagen Conclusion For the first time, mutations in COL4A5 gene were identified in Chinese AS patients in the mainland of China Two small deletions were detected, one of which was accompanied by two silent mutations No major gene deletion or rearrangement was detected The heterozygote status of one patient′s mother was also demonstrated by PCR SSCP analysis更多还原