[Genetic analysis of a 45,X male fetus].

Objective: To analyze the prenatal diagnosis procedure for a 45,X male fetus.

Methods: A 31-year-old women underwent amniocentesis due to a moderate risk of trisomy 21. The fetal cells were subjected to chromosomal karyotyping, BACs-on-Beads (BoBs) assay, chromosomal microarray analysis and fluorescence in situ hybridization.

Results: Combined analyses revealed that the whole of Yp has translocated to 21p, which yielded a fetal karyotype of 45,X,dic(Y;21)(q11;p11).ishdic(Y;21)(SRY+,CEPY+;CEP21+).

Conclusion: BoBs and modified N-banding method are helpful for the diagnosis of 45,X male fetus with Yp translocation.