Sex chromosome mosaicism in gonads of a fetus with cystic hygroma and deletion of the short arm of Y chromosome including loss of SRY.
The SRY gene on the short arm of the Y chromosome is necessary for male development. Without SRY, patients with 46,XY karyotype develop as females, fail to achieve normal puberty and have dysgenic gonads and a high incidence of gonadoblastoma. Here we report a female fetus, aborted at 17 weeks of pregnancy, with a non-mosaic 46,X,del(Y)(p11.2).ish del(Y)(SRY-) karyotype diagnosed by classical cytogenetics and fluorescence in situ hybridization (FISH). Ovarian tissue was full of oocytes and mitotic figures. FISH studies of ovarian tissues with X and Y centromere probes revealed extensive sex chromosome mosaicism, manifested by loss of the Y chromosome and polysomy of the X chromosome. We propose that X chromosome polysomy is a post-zygotic event that arises to facilitate gonadal differentiation in the absence of all factors necessary for normal gonadal development.
Aviv
H
H
Center for Human and Molecular Genetics, UMDNJ-New Jersey Medical School, Newark, New Jersey 07103, USA. avivha@umdnj.edu
Heller
D
D
Fajardo
A
A
Hoot
A
A
Mavaro
L
L
D000028:Abortion, Induced; D000328:Adult; D002872:Chromosome Deletion; D004268:DNA-Binding Proteins / Q000235:genetics*; D017809:Fatal Outcome; D005260:Female; D005313:Fetal Death; D005333:Fetus; D006066:Gonads / Q000378:metabolism*; D006801:Humans; D007621:Karyotyping; D018191:Lymphangioma, Cystic / Q000473:pathology*; D009030:Mosaicism; D009687:Nuclear Proteins; D011247:Pregnancy; D012729:Sex Chromosome Aberrations; D051876:Sex-Determining Region Y Protein; D014157:Transcription Factors; D014960:X Chromosome / Q000235:genetics; D014998:Y Chromosome / Q000235:genetics*
D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C497745:SRY protein, human; D051876:Sex-Determining Region Y Protein; D014157:Transcription Factors