Prenatal diagnosis of chromosome abnormalities and nine microdeletion syndromes using both traditional karyotyping and BoBs

Objective: To evaluate a new prenatal diagnosis model of chromosomal abnormalities and nine microdeletion syndromes by using both traditional karyotyping and a newly-developed rapid prenatal diagnosis technology, BACs-on-Beads (BoBs) technique.

Methods: From June 2012 to December 2014, 807 pregnant women with high risk after screening or with other indicators, were performed amniocentesis. Traditional karyotyping and BoBs were employed simultaneously for prenatal diagnosis.

Results: Thirty-two cases with chromosome aneupoidies were successfully detected both by BoBs and karyotyping, including 18 cases of trisomy 21, 6 cases of trisomy 18, 1 case of trisomy 13, and 7 cases with sex chromosome abnormality. All 8 fetuses with chromosome structural abnormalities detected by karyotyping were missed by BoBs; while BoBs contributed more in detection of five microdeletion syndrome cases, including 3 cases of DiGeorge syndromes (two with microduplication and one with microdeletion), one case of Miller-Dieker syndrome, and one case of Wolf-Hirschhorn syndrome.

Conclusions: Combined use of traditional karyotyping and BoBs, is a rapid and effective prenatal diagnosis model that may enlarge our horizon on chromosomal diseases and should be widely used in future clinical service.