产前诊断46,XX睾丸型性发育异常胎儿1例并文献复习

Prenatal diagnosis of a fetus with 46,XX testicular disorder of sex development and literature review

目的 分析46,XX睾丸型性发育异常胎儿的基因型与表型,并进行文献复习。方法 1例超声提示胎儿颈后透明层增厚的孕妇来我院产前诊断中心咨询。因其符合产前诊断指征,遂行胎儿染色体核型检测、胎儿染色体基因芯片检测。以“46,XX男性综合征”、“产前诊断”、“46,XX睾丸型性发育异常”、“prenatal diagnosis”、“46,XX male syndrome”、“46,XX testicular disorder of sex development”为检索词,检索中国知网、万方数据库、PubMed数据库(建库至2023年2月底),选取产前诊断为46,XX睾丸型性发育异常胎儿且临床资料完整的文献进行复习并总结胎儿表型。结果 胎儿染色体核型正常(46,XX),基因芯片提示Yp11.31-p11.2区域拷贝数为1,大小为3299 kb,存在SRY基因,胎儿被诊断为46,XX睾丸型性发育异常。文献检索发现仅报道9例产前诊断为46,XX睾丸型发育异常(SRY基因阳性)胎儿,大部分(70%, 7/10)胎儿孕期无明显异常,其中3/10的胎儿存在结构异常或超声提示NT增厚,其中5/10孕妇存在高龄风险。结论 在产前诊断中,发现46,XX睾丸型性发育异常胎儿是极为罕见的。孕期46,XX睾丸型性发育异常胎儿无明显异常;由于CMA检测的局限性,部分46,XX睾丸型DSD胎儿(SRY基因阴性)会被漏诊,这些因素给产前诊断和遗传咨询带来极大的挑战。

Objective To analyze the genotypes and phenotypes of the fetus with 46,XX testicular disorder of sex development and review related literature.Methods A pregnant woman with increased nuchal translucency came to the prenatal diagnosis center for genetic counselling.Due to the prenatal diagnosis indications,fetal chromosome karyotype and chromosomal microarray analysis(CMA)were carried out.The literature search with"prenatal diagnosis","46,XX male syndrome","46,XX testicular disorder of sex development"as key words was conducted on CNKI(Chinese National Knowledge Infrastructure),Wanfang(Chinese)and PubMed.All literature databases were searched up to the end of December 2023.Literature about clinical data and genetic features of fetuses with 46,XX testicular disorder of sex development was summarized and reviewed.Results Fetal chromosome karyotype showed 46,XX;fetal CMA indicated one copy of Ypl1.31-pl1.2(3299 kb)(SRY positive).The fetus was diagnosed with 46,XX testicular disorder of sex development.For now only nine cases with prenatal diagnosis of 46,XX testicular disorder of sex development have been reported.Most cases(70%,7/10)didn't show abnormalities,3/10 of the fetuses had structural abnormalities and increased NT,5/10 pregnant women had the risk of advanced age.Conclusion The cases with the prenatal diagnosis of 46,XX testicular disorder of sex development are extremely rare.Most fetuses with 46,XX testicular disorder of sex development have no obvious abnormalities during the whole gestation period.Due to the limitation of CMA,fetuses with 46,XX testicular DSD(SRY negative)may be missed diagnosis.Those factors pose great challenges for prenatal diagnosis and genetic counselling.