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Updated: Nov 21, 2025

Exploring X Chromosomal Aberrations in Ovarian Cells by Using Fluorescence In Situ Hybridization
Published on: April 7, 2023
Detectable chromosome X mosaicism in males is rarely tolerated in peripheral leukocytes
Weiyin Zhou1,2, Shu-Hong Lin1, Sairah M Khan1
1Division of Cancer Epidemiology and Genetics, National Cancer Institute, 9609 Medical Center Drive, Rockville, MD, 20850, USA.
Abstract:
Age-related male Y and female X chromosome mosaicism is commonly observed in large population-based studies. To investigate the frequency of male X chromosome mosaicism, we scanned for deviations in chromosome X genotyping array intensity data in a population-based survey of 196,219 UK Biobank men. We detected 12 (0.006%) men with mosaic chromosome X gains ≥ 2 Mb and found no evidence for mosaic chromosome X loss, a level of detection substantially lower than for autosomes or other sex chromosomes. The rarity of chromosome X mosaicism in males relative to females reflects the importance of chromosome X gene dosage for leukocyte function.
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