中国汉族人群AR基因多态性与男性尿道下裂的相关性研究

目的：研究中国汉族人群中雄激素受体基因（AR）第一外显子上的（CAG）n多态性与男性尿道下裂发病风险的相关性。方法研究对象为342例男性尿道下裂患儿以及351例健康人。从外周血淋巴细胞中提取全基因组DNA，对AR基因上的第一外显子（CAG）n进行PCR扩增，扩增产物以Sanger测序方法对其测序，计算各样本的（CAG）n分布情况。采用卡方检验（Chi-square test）比较病例组与对照组之间的（CAG）n分布，并分析（CAG）n对男性尿道下裂发病风险的影响。结果病例组（CAG）n为15～44，平均长度23．65±3．36；对照组为19～31，平均长度23．14±1．87，两组CAG重复序列有明显统计学差异（P＝0.013）。当n≥23，24，25，26时，尿道下裂发病风险分别为1．47（CI：1．081～2．001），1．356（CI：1．004～1．830），1．484（CI：1．063～2．071），1．565（CI：1．034～2．369），各组均有明显统计学意义（P＜0.05）；而当n≤19时，尿道下裂患病风险为2．111（CI：0．935～4．767），P＝0.05。结论 AR基因第一外显子上的（CAG）n与男性尿道下裂发病有明显的相关性，CAG重复序列越长，尿道下裂的发病风险越高。

The CAG repeat polymorphism in the Androgen Receptor gene regulates the risk of hypospadias in ChineseHan population

Objetive To analyze the risk for hypospadias in Han Chinese modified by the CAG repeat polymorphismintheexon1ofAndrogenReceptorgene.Methods DNAwasextractedformperipheralblood samples which came from 342 cases with hypospadias and 351 healthy voluntary anonymous blood sample do-nors.The CAG repeat lengths were amplified with PCR,which were calculated the difference between the hy-pospadiasandcontrolgroupusingChi-squaretest.Results ThemeanlengthofCAGinhypospadiaswas 23.65 ±3.36 （range 1 5 -44）,and it was 23.1 4 ±1 .87 （range 1 9 -31 ）in control group.A significant in-crease of the CAG repeat length in hypospadias group was detected when compared with the controls （P=0.01 3 ）.In addition,the odds ratios between the hypospadias and controls revealed that the hypospadias cases are about 1 .5 times to have longer CAG repeats than a shorter length for each repeat length investigated. Con-clusion WehaveinvestigatedalargenumberofhypospadiascaseswithregardstotheCAGrepeatlength,and we provided evidence that a higher number of the CAG repeat sequence in the AR gene have a clear effect on the risk of hypospadias in Han Chinese.