摘要
目的 探讨孕早期孕早期Down’s综合征的产前筛查及产前诊断方案。方法 时间分辨荧光免疫法 (TRFIA)对孕 8- 13w的 5 ,4 33例孕妇血清中的 β -hCG、PAPP -A2种血清标记物进行检测 ,筛查出 8例DS胎儿 (通过绒毛染色体核型分析和STR -PCR分析明确诊断 ) ;比较分析 8例DS胎儿母血清与 184例对照病例血清中两种标记物水平。结果 DS组母血中 β-hCG、PAPP -A水平均值分别为 2 .31MoM和 0 .4 2MoM ,与对照组差别有显著性意义 ( P <0 .0 5 ) ;β -hCG、PAPP-A两项指标联合筛查 ,DS的阳性检出率为 75 % ,假阳性率为 8.35 % ;有 7例DS胎儿经绒毛染色体核型分析确诊 ,3例DS胎儿经PCR -STR分析确诊。结论 孕早期 β -hCG、PAPP -A两联标记物筛查DS可以达到孕中期三联标记物筛查效果 ;
Objective: To Investigate the performance of first-trimester prenatal screening and diagnosis for Down's syndrome. Methods: Maternal serum were collected from 5433 pregnant women between 8 and 13 weeks gestation ,prior to having a chorionic villus sampling procedure. Free β glycoprotein sub-units of human chorionic gonadotrophin(β-hCG) , pregnancy- associated plasma protein(PAPP-A) were measured using time resolued fluorescence immunoassay (TRFIA). 8 pregnancies women with Down's syndrome were diagnosis using karyotype and polymerase chain reaction with polymorphic short tandem repeat markers (PCR-STR ).The levels of two markers was analyzed between 8 pregnancies women with DS and 184 control pregnancies women. Results: The levels of markers differed between affected and unaffected pregnancies sufficiently.The median freeβ-hCG level in affected pregnancies was 2.31 times the median level for unaffected pregnancies,and the median PAPP-A level was 0.42 times the unaffected median.The combination of the two markers estimate a women's risk of having a fetus with Down's syndrome.A screening programme that used a risk cutoff level of 1:250 would detect 75% 0f affected pregnancies and a 8.35% false- positive rate.Out of affected pregnancies ,7 pregnancies with Down's syndrome were diagnosed using karyotype,3 affected pregnancies were diagnosed using PCR- STR. Conclusion The performance of screening using maternal serum freeβ-hCG and PAPP-A at first-trimester was similar to the triple test at second trimester.The combination of cytogenetics and molecular genetics analyses may provide the success rate and the veracity of prenal diagnosis.
出处
《中国优生与遗传杂志》
2004年第5期42-44,共3页
Chinese Journal of Birth Health & Heredity
基金
河南省医学科技创新人才工程项目 ( 2 0 0 186)
