CAJ | 학술논문

目的：探讨胎儿标记染色体及衍生染色体的产前诊断与评估策略。方法通过传统染色体显带技术、荧光原位杂交（fluorescence in situ hybridization，FISH）及光谱核型分析（spectral karyotyping，SKY）等3种技术平台的联合应用，对2010年3月12日至2012年11月9日在中山大学附属第一医院检出的5例胎儿标记染色体及1例胎儿衍生染色体孕妇进行细胞与分子遗传学水平诊断的情况进行回顾性分析。结合胎儿的超声检查结果，评估2种染色体异常的临床表型效应及妊娠结局。结果5例标记染色体均为新发性突变，2例为镶嵌体，3例为非镶嵌体。其中2例为47,XX,+mar型标记染色体，超声检查提示胎儿异常，通过FISH及SKY确定其分别来源于4号和22号染色体；其余3例为Turner综合征型标记染色体，超声检查提示胎儿未见异常。这3例中，2例行FISH检测，证实标记染色体来源于Y染色体；1例行FISH和SKY检测，证实为环状X染色体。1例衍生染色体为新发性突变，行FISH及SKY证实为2号和6号染色体间相互易位形成的衍生染色体。5例标记染色体胎儿及1例衍生染色体胎儿均于妊娠25~32周选择引产。结论传统染色体显带技术、FISH及SKY等3种技术平台联合应用，可以准确诊断胎儿标记染色体及衍生染色体的来源及其所含的部分染色体成分。结合超声检查结果，可以为临床表型效应的评估及临床遗传咨询提供指导。
목적：탐토태인표기염색체급연생염색체적산전진단여평고책략。방법통과전통염색체현대기술、형광원위잡교（fluorescence in situ hybridization，FISH）급광보핵형분석（spectral karyotyping，SKY）등3충기술평태적연합응용，대2010년3월12일지2012년11월9일재중산대학부속제일의원검출적5례태인표기염색체급1례태인연생염색체잉부진행세포여분자유전학수평진단적정황진행회고성분석。결합태인적초성검사결과，평고2충염색체이상적림상표형효응급임신결국。결과5례표기염색체균위신발성돌변，2례위양감체，3례위비양감체。기중2례위47,XX,+mar형표기염색체，초성검사제시태인이상，통과FISH급SKY학정기분별래원우4호화22호염색체；기여3례위Turner종합정형표기염색체，초성검사제시태인미견이상。저3례중，2례행FISH검측，증실표기염색체래원우Y염색체；1례행FISH화SKY검측，증실위배상X염색체。1례연생염색체위신발성돌변，행FISH급SKY증실위2호화6호염색체간상호역위형성적연생염색체。5례표기염색체태인급1례연생염색체태인균우임신25~32주선택인산。결론전통염색체현대기술、FISH급SKY등3충기술평태연합응용，가이준학진단태인표기염색체급연생염색체적래원급기소함적부분염색체성분。결합초성검사결과，가이위림상표형효응적평고급림상유전자순제공지도。
Objective To investigate the prenatal diagnosis and phenotypic assessment strategies for fetal supernumerary marker chromosomes and derivative chromosomes. Methods Five cases of fetal supernumerary marker chromosomes and one case of fetal derivative chromosomes were diagnosed in the First Affiliated Hospital of Sun Yat-Sen University from March 12, 2010 to November 9, 2012 by conventional chromosome banding, fluorescence in situ hybridization (FISH) and spectral karyotyping (SKY). These cases were retrospectively reviewed. Combined with the results of ultrasonography, abnormal phenotypes and pregnancy outcomes were evaluated in these cases. Results All of the five supernumerary marker chromosomes were de novo, in which two were mosaic and the remaining three cases were non-mosaic. Of these five cases, two were type 47, XX+mar and ultrasound indicated abnormal phenotypes. FISH and SKY confirmed that they were derived from chromosome 4 and 22, respectively. The other three cases were marker chromosome with Turner syndrome karyotype (abnormal phenotypes were not found by ultrasound), in which two cases were derived from chromosome Y (by FISH) and one case was identified as ring chromosome X (by FISH and SKY). One de novo derivative chromosome was verified as a product of reciprocal translocation between chromosome 2 and 6 (by FISH and SKY). Induced abortion was performed in all cases between 25 and 32 gestational weeks. Conclusions By combining conventional chromosome banding, FISH and SKY, the origin and content of supernumerary marker chromosomes and derivative chromosomes can be identified. On this basis, clinical phenotype evaluation and genetic counseling may be offered with the ultrasonographic result.