广西地区唐氏综合征干预分析

Analysis on intervention of Down's syndrome in Guangxi

目的：探讨广西地区唐氏综合征（Downsyndrome，DS）妊娠临床特点、筛查价值及短串联重复序（Shorttan—demrepeat，STR）分析快速产前诊断的可行性。方法：对29946例产前诊断孕妇的绒毛、羊水或脐血进行染色体核型分析，采用荧光定量PCR法分析97例标本21号染色体5个STR。结果：Ds总检出率为0．89％，其中绒毛、羊水或脐血Ds检出率分别为0．39％、0．76％和1．39％。主要指征为血清Ds筛查高风险、高龄和超声异常发现，其Ds检出率分别为1．10％、0．65％和2．03％，其他指征合并以上3种指征者Ds检出率分别为1．69％、1．72％和3．75％。DS再发风险率为1．15％，其余指征组检出率为0～0．77％。STR分析显示21号染色三体核型18例，与染色体核型结果一致。结论：广西地区Ds主要在妊娠中晚期确诊，常规筛查方案能有效检出Ds，多项产前诊断指征者提示胎儿DS风险较大，STR位点可用于Ds快速产前诊断。

Objective： To explore the clinical characteristics and screening value of pregnancy combined with Down＇s syndrome （DS）, analyze the feasibility of rapid prenatal diagnosis with short tandem repeat （STR） . Methods： Chromosome karyotype analysis was conducted in chorionic villi, amniotic fluid and umbilical cord blood specimens of 29 946 pregnant women during prenatal diagnosis, fluores- cence quantitative PCR was used to analyze five STRs in chromosome 21 of 97 specimens. Results： The total detection rate of DS was 0. 89%, and the detection rates of DS in chorionic villi, amniotic fluid and umbilical cord blood specimens were 0. 39%, 0. 76% and 1.39%, respectively. The main indications included high risk of serum DS screening, advanced age and abnormal ultrasonic manifestations, the detection rates of DS were 1.10% , 0. 65% and 2. 03% , respectively; the detection rates of DS in women with the other indications com- bined with the above - mentioned indications were 1.69% , 1.72% and 3.75% , respectively. The risk ratio of DS recurrence was 1.15% , the detection rates of DS in women with the other indications ranged from 0 to 0. 77%. STR analysis found 18 women with trisomy 21, the re- sult was as the same as chromosome karyotype analysis. Conclusion： DS is mainly diagnosed definitely during the second and the third tri- mesters of pregnancy in Guangxi, routine screening scheme can effectively screen out DS, DS risk of fetuses born by the women with multiple indications of prenatal diagnosis is high, STR can be used for rapid prenatal diagnosis of DS.