目的 通过对尿道下裂患儿染色体核型分析和SRY基因检测,初步明确染色体核型、SRY基因缺失情况和尿道下裂之间的关系。 方法 采用染色体核型Leica CytoVision自动细胞遗传学分析系统进行染色体核型分析。采用PCR扩增琼脂糖凝胶电泳方法对SRY基因进行检测。 结果 137例尿道下裂患儿中,检测出染色体异常10例(7.29%),其中Ⅰ型2例(2/46,4.3%),Ⅱ型3例(3/41,7.3%),Ⅲ型2例(2/26,7.6%),Ⅳ型3例(3/24,12.5%),1例患儿SRY检测阴性,染色体检测45, XY,-21[10]/46, XY, r(21)[5]/ 46, XY, r(21; 21)[13],行双侧睾丸活检,双侧活检均有睾丸组织和卵巢组织,为DSD(disorders of sex development),其余病例未发现有SRY异常。 结论 染色体和核型改变是尿道下裂形成的主要原因之一,已确定可引起尿道下裂的染色体畸变有十余种,对于外生殖器分化模糊,如伴尿道下裂、阴蒂肥大呈阴茎样,根据生殖器外观常难以正确决定性别的患者,通过性染色体检查有助于做出明确诊断,并根据染色体检查结果和临床其它检查,明确是否DSD。
Objective To preliminarily determine the relationship between chromosomal and karyotypic detection and hypospadias. Methods The chromosomes and karyotypes were detected by an automatic analyzer. Results Chromosomal detection of hypospadias was abnormal(10/137, 7.29%). And the clinical types were I(2/46, 4.3%),Ⅱ(3/41,7.3%), Ⅲ(2/26,7.6%)and Ⅳ(3/24,12.5%). SRY detection was negative(n=1)with a genotype of 45, xy21/46, xyr(21)/46, xy, r(21; 21), bilateral testicular biopsy revealed both testicular and ovarian tissues. The diagnosis was disorder of sex development. Conclusion Chromosome and karyotype changes may predispose to the formation of hypospadias. So far a dozen types chromosomal aberrations have been identified. For differentiating vague external genitalias, such as hypospadias and penis-like clitoral enlargement, gender is often difficult to determine. An examination of sex chromosomes helps to make a definite diagnosis. Based upon the results of chromosomal testing and clinical examinations, disorder of sex development is ascertained.
