河南地区586例染色体相互易位的热点断裂区域分析

目的分析河南地区人群染色体相互易位的发生率、常见易位的染色体和核型以及断裂区域,并探讨不同断裂区域对河南地区人群妊娠史或发育史的影响。方法对2016年2月至2018年4月因不孕不育、自然流产、反复流产、死胎等不良妊娠史或发育异常到郑州大学第一附属医院遗传与产前诊断中心遗传咨询和检查的62477例患者进行外周血淋巴细胞染色体核型分析,对染色体相互易位的发生率、常见相互易位的染色体和核型以及断裂区域进行统计。结果62477受检者中共检测出586例染色体相互易位携带者,发生率为0.94%。染色体相互易位群体中,572例染色体相互易位携带者为不孕症患者,发生率为0.92%,14例为发育异常患者,发生率为0.02%。染色体累及次数显示,1号、4号、7号和11号相互易位染色体累及次数最多;核型t(11;22)(q25;q13)累及次数最多。断裂区域分析显示,相互易位染色体共累及出现437个断裂区域,其中11q23、22q13和1p36累及次数最多,且引起携带者不孕不育、流产、胚胎停止发育、先天畸形、发育迟缓/智力低下或表型正常等。结论河南地区染色体相互易位不孕症携带者的发生率为0.92%。断裂区域分析结果表明相互易位累及的染色体及其断裂区域对携带者的妊娠或发育存在影响。探讨相互易位染色体的断裂区域能为携带者提供准确的遗传、生殖和发育咨询,也为阐述断裂区域附近基因功能和寻找新基因及其作用机制提供参考依据。

Analysis for common chromosomal breakpoint regions among 586 carriers of reciprocal translocations from Henan Province

Objective To determine the frequency,common chromosomal karyotypes and breakpoints,and involved regions among carriers of reciprocal translocations from Henan Province,and to explore the influence of common breakpoint regions on pregnancy and fetal development.Methods For 586 carriers of reciprocal translocations,the above features were retrospectively analyzed.Results The 586 reciprocal translocations were identified among 62477 subjects,which yielded a frequency of 0.94%.Among these,572(0.92%)had abnormal fertility,and 14(0.02%)had a history of abnormal fetal development.Statistical analysis showed that chromosomes 1,4,7 and 11 were most frequently involved,with t(11;22)(q25;q13)being the most common type of translocation.In total 437 breakpoint regions were identified,with 11q23,22q13 and 1p36 being most frequently involved,which resulted in infertility,abortion,embryo death,congenital malformation,development delay,mental retardation or a normal phenotype.Conclusion Above results indicated a 0.92%carrier rate for reciprocal chromosomal translocations in Henan.The location of breakpoint regions may affect the pregnancy and/or fetal development.Discovery of such regions may enable more accurate genetic,reproductive and developmental counseling for carriers,and provide reference for delineation of function and pathogenetic mechanism of the relevant genes.