Delineation of an isodicentric Y chromosome in a mosaic 45,X/46,X,idic(Y)(qter-p11.3::p11.3-qter) fetus by SRY sequencing, G-banding, FISH, SKY and study of distribution in different tissues.
Many factors such as genetic, developmental and hormonal are involved in mammalian sex determination. The relative importance and the mutual interactions among those factors are obscure. Study of cytogenetic mosaicism involving sex chromosomes may help to further unravel the mysterious process. We report a fetus with a mosaic karyotype, 45,X/46,X,idic(Y)(qter-p11.3::p11.3-qter), with unambiguous male external genitalia and a defect in the interventricular septum of the heart. Genotype of this fetus was extensively studied by technologies including sequencing of SRY (sex-determining region on the Y chromosome) gene, G-banding, FISH (fluorescence in situ hybridization) and SKY (spectral karyotyping). A markedly higher percentage of Y-containing cells was observed in the gonads (55%) than in the amniotic fluid (17%) and placental villi (11%), which was considered to be the major reason why the fetus did not have ambiguous genitalia.
Wu
Hsuan-Hsuan
HH
Center for Health Promotion and Department of Family Medicine, Changhua Christian Hospital, Changhua, and Department of Obstetrics and Gynecology, College of Medicine, Taipei, Taiwan.
Lee
Tsung-Hsien
TH
Chen
Chin-Der
CD
Yeh
Kun-Tu
KT
Chen
Ming
M
D000328:Adult; D000649:Amniocentesis; D000653:Amniotic Fluid / Q000166:cytology; D002824:Chorionic Villi; D002871:Chromosome Banding; D041321:Chromosomes, Human, X / Q000235:genetics*; D041322:Chromosomes, Human, Y / Q000235:genetics*; D005260:Female; D005333:Fetus; D024282:Genes, sry; D006066:Gonads / Q000166:cytology; D006345:Heart Septal Defects, Ventricular / Q000235:genetics; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D018404:Isochromosomes; D008297:Male; D009030:Mosaicism; D011247:Pregnancy; D051876:Sex-Determining Region Y Protein / Q000235:genetics*; D032681:Spectral Karyotyping
D051876:Sex-Determining Region Y Protein