[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.