OBJECTIVETo assess the application value in prenatal diagnosis using karyotype analysis combined with BACs-on-Beads (BoBs) assay.

METHODSNine hundred sixty five pregnant women were subjected to amniocentesis, chromosomal karyotype analysis and detection of BoBs were employed simultaneously for abnormal number of chromosomes and 9 chromosome microdeletion syndrome in prenatal diagnosis.

RESULTSFifty cases common chromosome aneupoidies were successfully detected by both karyotype analysis and BoBs which included 31 cases of trisomy 21,10 cases of trisomy 18 and 9 cases with sex chromosome abnormality. BoBs in addition detected 1 case of DiGeorge-1 microdeletion syndrome and 1 case of 7q11.23 microduplication syndrome. All 9 fetuses with chromosome abnormalities detected by karyotyping were missed by BoBs, including 2 cases of marker chromosomes,4 cases of chromosomal translocation,1 case of chromosomal inversion, 2 cases of Sex chromosome mosaicism; 2 cases of fetal inherited from the parents,7 cases for novel mutations.

CONCLUSIONKaryotype analysis combined with BoBs dedtection is a rapid, effective and highly accurate prenatal diagnosis model that may should be widely used in clinical diagnosis.