Study Finds Age-Related Loss of Y Chromosome in Men May Increase Mortality Risk

Recent research shows that age-related loss of the Y Chromosome in men may have significant health consequences, challenging earlier beliefs that it had limited importance beyond male development. This phenomenon, known as mosaic loss of Y, becomes increasingly common with age, affecting nearly 40% of men in their 60s and over half by age 90.

Rather than occurring in all cells, the loss creates a mix of normal and Y-deficient cells. Once the chromosome is lost in a cell, all subsequent copies lack it. Studies suggest these altered cells may proliferate faster, potentially contributing to tissue changes and disease progression.

Growing evidence links Y chromosome loss to serious conditions, including Cardiovascular Disease, Alzheimer’s Disease, and various cancers. Men with higher levels of Y-deficient cells show increased risks of heart attacks, neurodegeneration, and poorer cancer outcomes. It has also been associated with worse outcomes in COVID-19.

The underlying mechanisms may involve disrupted gene regulation. Although the Y chromosome contains relatively few genes, some act as tumor suppressors or regulate immune and cellular functions. Losing these genes may impair normal biological processes, including inflammation control and tissue repair.

Environmental factors such as smoking and exposure to toxins can accelerate Y chromosome loss, while genetic predisposition also plays a role. Experimental studies further suggest a causal link, with Y-deficient cells contributing to heart dysfunction and disease progression.

Overall, the findings indicate that the Y chromosome plays a broader role in maintaining health than previously thought. Understanding its loss could open new avenues for disease prediction, prevention, and targeted therapies in aging men.

REFERENCE: The Conversation. "Men are losing a key chromosome with age and it may be deadly." ScienceDaily. ScienceDaily, 20 March 2026. .