荧光原位杂交法快速诊断早孕期常见染色体数目畸变

Rapid Detection of Numerical Aberrations of Chromosomes in the First Trimester of Pregnancy by Using Fluorescence in Situ Hybridization(FISH)

荧光原位杂交技术（ｆｌｕｏｒｅｓｃｅｎｃｅｉｎｓｉｔｕｈｙｂｒｉｄｉｚａｔｉｏｎ，ＦＩＳＨ）已逐步应用于产前常见染色体数目畸变诊断。本文报道应用１３、１８和２１号染色体区域特异性探针对５２８例未经培养的早孕期绒毛间质细胞进行原位杂交，并同时行常规细胞遗传学分析以平行诊断。结果表明，探针相应的染色体数目正常标本中，只有约１％（０～１８％）间期核呈现三个杂交信号，而在三体或三倍体细胞标本中显示三个杂支信号的细胞核比例１３三体为７０％（５２％～８４％），１８三体为７３％（６８％～８４％），２１三体为７６％（５４％～９０％）（包括１例嵌合体）。整个实验过程仅需２４ｈ左右。因此，荧光原位杂交法在早孕期可快速准确诊断胎儿染色体数目畸变。

Fluorescence in situ hybridization(FISH)has been applied for rapid prenatal diagnosis of common numerical aberrations of Chromosomes.We used FISH with Chromosome 13,18 and 21 specific probes on 528 uncultured mesenchymal chorionic villi cell samples to detect the chromosomal abnormalities,and we also performed the conventional chromosome analysis of cultured cells from parallel samples.The results showed,in samples disomic with respect to the probed chromosomes,and average of 1 percent(range 0-18 percent)had three hybridization signals.By contrast,in the samples trisomic or triploidic for the probed chromosomes,an average of 70 percent(52-84 percent)(chromosome 13),73 percent(68-84 percent)(chromosome 18),and 76 percent(54-90 percent)(chromosome 21,including one case of mosaic trisomy 21)of the nuclei displayed three signals.The whole test took about 24 hours.We concluded that FISH can provide a rapid and accurate method for the first trimester prenatal idetification of selected numerical aberrations of chromosomes.