产前诊断中羊水嵌合体形成机制的探讨

目的探讨产前诊断中羊水嵌合体形成的机制,便于临床医生在遗传咨询中正确处理羊水培养中出现的嵌合现象。方法 2004年1月至2010年4月对在中山大学附属第一医院胎儿医学中心因各种产前诊断指征就诊的患者行羊膜腔穿刺术取羊水做染色体检查,从中选取羊水染色体为嵌合体的患者穿刺脐血复查染色体,结合两者的结果探讨羊水嵌合体形成机制。结果羊水嵌合体检出33例,其中25例为假嵌合体,8例为真嵌合体,7例真嵌合体羊水结果与脐血结果一致,1例真嵌合体两者结果不一致。结论正确判断羊水培养中出现的真假嵌合体及其风险,对产前诊断和遗传咨询具有重要的意义。

Investigation of mechanism of formation of amniotic fluid mosaicism in prenatal diagnosis

Objective：To investigate the mechanism of formation of amniotic fluid mosaicism in prenatal diagnosis,in order to help the clinicians handle the mosaicism which appears in amniotic fluid culture correctly in genetic counseling.Methods：From January 2004 to April 2010 in Fetal Medicine Center of the First Affiliated Hospital of Sun Yat-sen University amniotic fluid was obtained from patients with various indications of prenatal diagnosis by amniocentesis for karyotyping,then cord blood was obtained from patients with amniotic fluid mosaicism,the results were combined to investigate the mechanism of formation of amniotic fluid mosaicism.Results：Out of 33 cases of detected amniotic fluid mosaicism,25 cases were pseudo-mosaicism,8 cases of true mosaicism,7 cases of true mosaicism were consistent in amniotic fluid and cord blood results,one case of inconsistency between amniotic fluid result and cord blood result.Conclusion：It is significant for prenatal diagnosis and genetic counseling to judge true and pseudo-mosaicism and their risks correctly in amniotic fluid culture.