Identification of Y chromatin directly in gonadal tissue by fluorescence in situ hybridization (FISH): significance for Ullrich-Turner syndrome screening in the cytogenetics laboratory.
The presence of Y chromatin in individuals with Ullrich-Turner syndrome (UTS) confers a risk for gonadoblastoma. In mosaic cases, little is known about Y chromatin distribution in gonads. Fluorescence in situ hybridization (FISH) is a direct approach to assess the extent of Y chromatin mosaicism in gonads. Gonadal tissue from four patients with mosaic karyotypes were analyzed by routine cytogenetics and FISH with X and Y centromere probes. Y chromatin was present in gonads in varying percentages in these patients. The distribution of Y chromatin in gonads of UTS individuals did not completely correlate with that found in blood lymphocytes. The finding of Y chromatin in the blood samples from these patients prompted the development of a screening strategy in our cytogenetics laboratory to detect low-level Y chromatin mosaicism in patients with UTS.
Atkins
K E
KE
Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA.
Gregg
A
A
Spikes
A S
AS
Bacino
C A
CA
Bejjani
B A
BA
Kirkland
J
J
Shaffer
L G
LG
D000293:Adolescent; D002648:Child; D002843:Chromatin; D005260:Female; D005820:Genetic Testing; D018238:Gonadoblastoma / Q000235:genetics; D006066:Gonads / Q000737:chemistry*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D009030:Mosaicism / Q000235:genetics*; D009634:Noonan Syndrome / Q000235:genetics*; D014998:Y Chromosome / Q000235:genetics*
D002843:Chromatin