9号染色体臂间倒位的遗传效应及产前诊断的重要性

目的:探讨9号染色体臂间倒位的临床效应及产前诊断的重要性。方法:取不良孕产史患者外周血行染色体核型分析;9号染色体臂间倒位患者再次妊娠时于妊娠16～20周抽取羊水或妊娠22～32周抽取脐静脉血进行染色体核型分析,按常规方法行淋巴细胞培养,制备染色体,应用G显带和C显带技术进行核型分析。结果:1468例(734对)不良孕产史夫妇行外周血染色体检查,发现9号染色体臂间倒位21例,检出率为1.43%,明显高于一般人群9号染色体臂间倒位的发生率。9例患者再次妊娠时行胎儿染色体检查进行产前诊断,9号染色体臂间倒位3例,唐氏综合征1例,16号染色体长臂次缢痕增加1例。B超检查为畸形儿引产2例。结论:9号染色体臂间倒位可导致异常生育,应引起重视,对携带者再次妊娠应行产前诊断。

Genetic effect of pericentric inversion of chromosome 9 and the importance of prenatal diagnosis

Objective: To explore the clinical effect of pericentric inversion of chromosome 9 and the importance of prenatal diag- nosis. Methods: The peripheral blood of patients with adverse pregnancy history was abstracted for karyotype analysis; for the patients of repeated pregnancy with pericentric inversion of chromosome 9,amniotic fluid during 16 ～ 20 gestational weeks or umbilical vein during 22 ～ 32 gestational weeks were abstracted for karyotype analysis,lymphocytes were cultured routinely,then chromosome 9 was prepared,G banding and C banding techniques were used for karyotype analysis. Results: 1 468 cases ( 734 couples) with adverse pregnancy history received chromosomal examination of peripheral blood,21 cases were found with pericentric inversion of chromosome 9,the detection rate was 1. 43% ,which was significantly higher than that of general population. Among 21 cases,9 cases received chromosomal examination for prenatal diagnosis in subsequent pregnancy,3 cases were found with pericentric inversion of chromosome 9,1 case was found with Down syn- drome and 1 case was found with secondary constriction increase of long arm of chromosome 16; 2 cases were diagnosed as deformed children by ultrasound,then induction abortion was conducted. Conclusion: Pericentric inversion of chromosome 9 can result in abnormal fertility, which should be paid attention to,carriers of the disease should receive prenatal diagnosis in subsequent pregnancy.