应用MLPA亚端粒检测技术分析妊娠失败的遗传学原因

Analysis of the cause of pregnancy failure with combined MLPA assay for subtelomeric regions and ultrasonography

目的探讨多重连接依赖探针扩增（multiplex ligation dependent probe amplification，MLPA）技术在分析流产组织染色体异常中的应用，分析染色体异常与超声指标的相关性，对不明原因流产的遗传学因素进行评估。方法收集421例自然流产、宫内死胎和用超声异常终止妊娠的样本，用MLPA的P036、P070试剂盒进行检测。结果在421例流产样本中，MLPA提示异常者有232例，占55．11％。在孕13周前的286例样本中，有206例存在异常，比例高达72．03％，在孕14～19周的49例样本中，有14例检出异常，占28．57％。在孕20周及以后的86例样本中，有12例检出异常，占13．95％。在117例超声提示胎儿存在畸形或异常的样本中，有33例检测出异常，占28．21％。其中28例为染色体数目异常、4例为染色体微缺失和／或微重复、1例同时存在数目异常和微重复。在颈部超声异常、胎儿水肿综合征、多发畸形、消化系统异常组中，MLPA检测的阳性率分别为71．4％、58．8％、37．8％、9．1％。在心脏、神经、面部、骨骼和泌尿系统超声异常者中则未发现异常。结论在自然流产中，染色体数目异常占主要因素。随着孕周的增大，染色体异常与流产的关系逐渐减弱。联合应用超声检查和MLPA检测，可以有效地提升染色体异常的检出率。

Objective To explore the value of multiplex ligation-dependent probe amplification （MLPA） for the detection of chromosome abnormalities in miscarriage tissues, and to correlate the result with ultrasound findings. Methods A total of 421 cases of spontaneous abortions and fetal deaths were detected with the MLPA method. Results Among the 421 samples, 232 （55. 11%） had an abnormal MLPA result. For the 286 cases derived from 〈 13 weeks pregnancy, 206 （72.03%） were abnormal. For the 49 cases from 14 - 19 weeks pregnancy, 14 （28.57%） were abnormal. For the 86 cases derived after 20 weeks pregnancy, 12 （13. 95%） were abnormal. Among the 117 cases with abnormal ultrasound findings, 33 cases （28. 21%） had an abnormal MLPA result, 28 out of the 33 eases were numerical chromosome abnormality, 4 cases were chromosome microdeletion and/or micro duplication, 1 case had both numerical abnormality and microduplication. For those with abnormal ultrasound findings for the neck region, fetal edematous syndrome, multiple malformations and digestive system, the detection rates for MLPA were 71.4%, 58.8%, 37.8%, and 9.1%, respectively. For those with abnormal finding of cardiac system, nervous system, face, skeletal system and urinary system, none was found with positive results of MLPA. Conclusion Numerical chromosomal abnormalities account for the majority of cases with spontaneous abortion. With the increase of gestational age, the occurrence of chromosomal abnormalities gradually declines. Combined ultrasound and MLPA assay can improve the detection rate and accuracy for chromosomal abormalities.