[Prenatal diagnosis and genetic analysis of a fetus with der(X)t(X;Y)(p22.3;q11.2)].

Objective: To explore the pathogenesis and genetic characteristics of a fetus with a der(X)t(X;Y)(p22.3;q11.2) karyotype.

Methods: G-banding karyotyping analysis, BoBs (BACs-on-Beads) assay, and single nucleotide polymorphism array (SNP-array) were used to delineate the structural chromosomal aberration of the fetus. The parents of the fetus were also subjected to karyotyping analysis.

Results: The fetus and its mother were both found to have a karyotype of 46,X,add(X)(p22), while the father was normal. BoBs assay indicated that there was a lack of Xp22 but a gain of Yq11 signal. SNP-array confirmed that the fetus and its mother both had a 7.13 Mb deletion at Xp22.33p22.31 (608 021-7 736 547) and gain of a 12.52 Mb fragment at Yq11.221q11.23 (16 271 151-28 788 643).

Conclusion: The fetus was determined to have a karyotype of 46,X,der(X)t(X;Y)(p22.3;q11.2)mat. The combined use of various methods has facilitated delineation of the fetal chromosomal aberration and prediction of the risk prediction for subsequent pregnancy.