Aim： To identify the genotype of two Indians with male pseudohermaphroditism. Methods： Standard radioimmunoassay procedure was used for estimating hormonal levels. Conventional cytogenetic analysis was carded out fo...Aim： To identify the genotype of two Indians with male pseudohermaphroditism. Methods： Standard radioimmunoassay procedure was used for estimating hormonal levels. Conventional cytogenetic analysis was carded out for diagnosing the genetic sex in these subjects with genital ambiguity. Molecular analysis was carried out by standard polymerase chain reaction procedure using different sets of primers and reaction conditions specific for the 5α- reductase type 2 gene （SRDSA2） gene. Direct sequencing was carried out using the ABI Prism dye terminator sequencing kit and the ABI 310 sequencing apparatus. Results： We found an SRDSA2 gene mutation in exon 5, where arginine is substituted with glutamine （R246Q）, in two males with pseudohermaphroditism and ambiguous genitalia from unrelated families. This is the first time this mutation has been reported in individuals from India. Conclusion： Identification of the R246Q mutation of the SRDSA2 gene from two unrelated Indian families possibly extends the founder gene effect.展开更多
目的探讨类固醇5α-还原酶2型缺乏症(SRD5A2)的临床特点、基因突变特征。方法回顾分析1例以外阴异常为初诊表现的SRD5A2患儿的临床资料。结果患儿,2岁5个月,社会性别为女性。基础促黄体生成素(LH)0.07 m IU/mL、促卵泡激素(FSH)0.39 m I...目的探讨类固醇5α-还原酶2型缺乏症(SRD5A2)的临床特点、基因突变特征。方法回顾分析1例以外阴异常为初诊表现的SRD5A2患儿的临床资料。结果患儿,2岁5个月,社会性别为女性。基础促黄体生成素(LH)0.07 m IU/mL、促卵泡激素(FSH)0.39 m IU/mL;人绒毛膜促性腺激素(HCG)刺激试验前后,睾酮分别是0.06 ng/mL、3.65ng/mL,双氢睾酮(DHT)分别是19.67 pg/mL、68.25 pg/mL;17-羟孕酮(17-OHP)1.20 ng/mL,雄烯二酮(A 2)0.07 ng/mL;HCG试验后T/DHT为51.72、T/A 2为14.70;抗苗勒管激素(AMH)22.97 ng/mL,抑制素B(INH-B)274.4 pg/mL。盆腔超声和磁共振均未探及子宫及卵巢。染色体为46,XY;性别决定(SRY)基因检测无异常;雄激素受体(AR)基因结果阴性。患儿及父母外周血均检测到2型5α-还原酶(SRD5A2)基因的致病性突变。应用2.5%DHT凝胶涂抹阴茎4个月后阴茎增长2 cm。结论 SRD5A2的诊断以HCG试验后T/DHT增高为主要依据,检测到致病性的SRD5A2基因突变可确诊。展开更多
文摘Aim： To identify the genotype of two Indians with male pseudohermaphroditism. Methods： Standard radioimmunoassay procedure was used for estimating hormonal levels. Conventional cytogenetic analysis was carded out for diagnosing the genetic sex in these subjects with genital ambiguity. Molecular analysis was carried out by standard polymerase chain reaction procedure using different sets of primers and reaction conditions specific for the 5α- reductase type 2 gene （SRDSA2） gene. Direct sequencing was carried out using the ABI Prism dye terminator sequencing kit and the ABI 310 sequencing apparatus. Results： We found an SRDSA2 gene mutation in exon 5, where arginine is substituted with glutamine （R246Q）, in two males with pseudohermaphroditism and ambiguous genitalia from unrelated families. This is the first time this mutation has been reported in individuals from India. Conclusion： Identification of the R246Q mutation of the SRDSA2 gene from two unrelated Indian families possibly extends the founder gene effect.
