Y chromosome loss in cancer research

Research from the University of Arizona Cancer Center has identified the loss of the Y chromosome in male cells as a potential early indicator of cancer. This phenomenon, described as ‘mosaic loss of Y chromosome’, involves daughter cells losing the chromosome during division, resulting in tissue where some cells possess the chromosome while others do not. Initial studies involving the analysis of 1,000 archived tissue samples from 405 men showed that Y chromosome loss was more pronounced within tumors and in the immediate vicinity of tumor tissue.

Subsequent findings have refined this understanding, suggesting that Y chromosome loss is a continuous spectrum of erosion rather than an all-or-nothing event. Researchers developed a ‘Y Erosion Score (YES)’ to measure this process and discovered that cancer cells selectively erode specific, gene-rich regions of the Y chromosome to facilitate tumor growth. The study identified 24 protein-coding genes on the Y chromosome that are recurrently lost, a finding supported by bladder tumor sequencing data.