Identification of Y chromatin directly in gonadal tissue by fluorescence in situ hybridization (FISH): significance for Ullrich-Turner syndrome screening in the cytogenetics laboratory

Am J Med Genet. 2000 Apr 24;91(5):377-82. doi: 10.1002/(sici)1096-8628(20000424)91:5<377::aid-ajmg11>3.0.co;2-8.

Abstract

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.

Publication types

  • Case Reports

MeSH terms

  • Adolescent
  • Child
  • Chromatin*
  • Female
  • Genetic Testing
  • Gonadoblastoma / genetics
  • Gonads / chemistry*
  • Humans
  • In Situ Hybridization, Fluorescence
  • Karyotyping
  • Mosaicism / genetics*
  • Noonan Syndrome / genetics*
  • Y Chromosome / genetics*

Substances

  • Chromatin