[Comparison of results of improved FISH and conventional karyotyping analysis of 2607 amniotic fluid samples]

To compare the results of fluorescence in situ hybridization (FISH) assay and conventional karyotyping analysis for the detection of chromosomal aneuploidies.

In total 2607 amniotic fluid samples were subjected to an improved FISH technique. Meanwhile, karyotype analysis was also ordered for each sample.

Of the 2607 samples, 62 abnormalities were identified by FISH, which included 62 cases of trisomy 21, 5 cases of 45,X, 12 cases of trisomy 18, 3 cases of trisomy 13, and 1 case of 47, XYY. Conventional karyotyping analysis has identified 63 cases of trisomy 21, 5 cases of 45,X, 12 cases of trisomy 18, 3 cases of trisomy 13, 1 case of 47, XYY, and 57 cases of balanced translocations. The success rate of FISH detection was 98.4% for trisomy 21, and 100% for 45,X, trisomy 18 and trisomy 13.

For the detection of chromosomal aneuploidies, FISH assay is quick, simple, accurate and can reduce workload when aminocyte culture has failed. As an auxiliary method for amniocytic analysis, it can provide reference for the consultation of those with advanced age and high pregnancy risk.