嵌合型Y染色体等臂双着丝粒致胎儿主动脉狭窄1例报告及文献复习

Aortic stenosis of fetus caused by chimeric Y-chromosome isobaric double-adherent granules:A case report and literature review

摘要

目的 通过对先天性主动脉狭窄（AS）胎儿产前诊断结果进行遗传学分析，明确其可能的致病原因。 方法 1例孕25周孕妇，因“胎儿AS”行羊膜腔穿刺术采集羊水，行染色体G显带核型分析联合单核苷酸多态性微阵列（SNP-array）检测。同时采集胎儿父母外周血，行染色体核型分析。 结果 胎儿核型分析，为嵌合型Y染色体等臂双着丝粒；SNP-array分析，胎儿染色体Yp11.31q11.21区段存在11.2 Mb片段的重复，同时Yq11.21q11.23区段存在14.8 Mb片段的缺失。胎儿父母均为正常核型，考虑其为新发变异。经充分遗传咨询后，孕妇及家属选择回当地引产。 结论 嵌合型Y染色体等臂双着丝粒的染色体核型可能是男性胎儿表型为AS的原因，羊水细胞染色体核型分析联合SNP-array检测有助于该病的早期诊断。

Abstract

Objective To confirm the potential etiological factors of congenital aortic stenosis （AS） by genetic analysis on prenatal diagnostic results of the fetus with AS. Methods Amniocentesis for chromosomal G-band karyotyping combinated with single nucleotide polymorphism array （SNP-array） analysis was conducted on the amniotic fluid collected from a 25-week pregnant woman diagnosed as “fetus AS”； chromosome karyotyping was also performed on the peripheral blood of the fetal parents. Results The fetal karyotype analysis showed a chimeric Y-chromosome isobaric double-adherent granules. The SNP-array analysis results revealed a 11.2 Mb duplication in the Yp11.31q11.21 region and a 14.8 Mb deletion in the Yq11.21q11.23 region. Both the parents presented a normal karyotype， suggesting it was a newfound mutation. After extensive genetic counseling， the pregnant woman and her family chose to terminate the pregnancy locally. Conclusion The chromosomal karyotype of the chimeric Y-chromosome isobaric double-adherent granules may be a contributing factor to the AS phenotype in the male fetus. The combined use of chromosomal karyotyping and SNP-array analysis on the amniotic cells is instrumental in the early diagnosis of the disease.

关键词

胎儿 / 先天性心脏病 / 主动脉狭窄 / 产前诊断 / 嵌合型Y染色体等臂双着丝粒

Key words

Fetus / Congenital heart disease / Aortic stenosis / Prenatal diagnosis / Chimeric Y-chromosome isobaric double-adherent granules

Author summay

全宇璐（1994－），女，河北省张家口市人，住院医师，医学硕士，主要从事生殖遗传学方面的研究。