[Application of BACs-on-Beads and karyotyping for the prenatal diagnosis of 1371 pregnant women with a high risk].

OBJECTIVE: To assess the value of combined BACs-on-BeadsTM (BoBs) and chromosomal karyotyping for the diagnosis of women with high-risk pregnancy.

METHODS: For 1371 women with singleton pregnancy and various indications for prenatal diagnosis, karyotyping and BoBs were simultaneously applied on their amnionic fluid samples.

RESULTS: In total 23 cases of trisomy 21, 11 cases of trisomy 18, 5 cases of sex chromosome aneuploidies, 6 cases of microdeletions/microduplications, 2 cases of chimeric chromosomes and 1 case of structural chromosomal abnormality were detected by the BoBs assay, among which the 6 microdeletions/microduplications were not detected by karyotyping. Karyotyping analysis has identified an extra yield of 19 chromosomal abnormalities and 34 chromosomal polymorphisms.

CONCLUSION: Combined use of BoBs and chromosomal karyotyping can improve the detection rate of fetal chromosomal abnormalities including microdeletions/microduplications, which should find a wider use in the clinics.