Prenatal diagnosis and genetic analysis of a female fetus with 46, XX and positive SRY gene / 中华围产医学杂志

ABSTRACT

We report a case of a pregnant woman with 46,XX karyotype and positive sex-determining region on the Y chromosome ( SRY) gene and her female fetus. Ultrasound examination at 12 +6 gestational weeks indicated a thickened fetal nuchal translucency, and 46, XX with a positive SRY gene was detected in the fetus through quantitative fluorescent-polymerase chain reaction and amniotic fluid karyotype. However, the ultrasound showed that the gender of the fetus was female, which was inconsistent with the phenotype of male syndrome with 46, XX combining positive SRY gene. The fluorescent in situ hybridization (FISH) revealed that the short arm of the Y chromosome translocated to the long arm of one of the X chromosomes, namely Yp11.3-Xq28. In addition, a copy number variation at Yp11.31p11.2 copy (about 1 MB) was found by chromosomal microarray analysis, which validated the result of FISH and was consistent with the mother. After genetic counseling, the parents chose to continue the pregnancy to full term, and no abnormalities were found in the infant during the follow-up.