Men lose Y chromosome with age: Scientists now link it to shorter lives and serious illness

The Disappearing Y: Why Ageing Men May Face Hidden Health Risks (Image: Canva)

Researchers have found that many older men gradually lose the Y chromosome in some body cells, a change once thought harmless. New evidence links this loss to heart disease, cancer, Alzheimer’s and higher COVID mortality. Rates rise with age, affecting 40% of 60 year olds and 57% of 90 year olds. Studies, including large population research and mouse experiments, suggest Y loss may directly affect immune function, cardiac health and cancer risk.

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Scientists are reporting that many ageing men gradually lose the Y chromosome from some body cells, a change increasingly linked to heart disease, cancer and shorter life expectancy.

Loss Of Y Chromosome In Older Men

Researchers once believed losing the Y mattered little. The chromosome carries relatively few genes. Its main role involves male sex determination. It also supports normal sperm development. Beyond that, it seemed largely dispensable.

New detection methods now reveal frequent loss. Studies show the trend rises sharply. About 40% of 60 year olds show loss. Among 90 year olds, rates reach 57%. Smoking and carcinogen exposure increase risk further.

Loss occurs only in certain cells. Descendant cells never regain the chromosome. This creates a mosaic within tissues. Some cells carry Y, others do not. Laboratory studies show Y less cells grow faster. That growth advantage may extend to tumours.

The Y is prone to division errors. It can be trapped in membrane fragments. Rapidly dividing tissues may lose it more. Scientists once doubted major health effects.

Health Risks Linked To Y Chromosome Loss

Evidence now links Y loss to illness. Cardiovascular and neurodegenerative diseases appear associated. Kidney cells lacking Y correlate with disease.

A large German study examined older men. Those above 60 showed striking findings. High Y loss increased heart attack risk. Loss has also been tied to COVID deaths. Researchers suggest this may explain sex gaps.

Alzheimer’s patients show higher Y loss rates. Some studies report tenfold frequency increases. Several cancers also show clear associations. Outcomes appear poorer among affected men. Cancer cells often lack Y entirely.

Yet association does not prove causation. Disease might trigger chromosome instability itself. A third factor may drive both processes. Genetic studies suggest partial inherited influence. Around 150 genes relate to cell cycle control.

Mouse experiments offer stronger clues. Scientists transplanted Y deficient blood cells. Irradiated mice then developed cardiac weakness. Heart failure appeared more frequently. Eye melanoma may also link directly.

Why The Y Chromosome Matters

The human Y holds 51 coding genes. Other chromosomes contain thousands of genes. The male determining SRY gene acts widely. Some link it to Parkinson’s disease.

Four sperm genes function only in testes. However, 46 additional genes show wider roles. Several act as cancer suppressors. Most have matching copies on X chromosomes.

When Y disappears, regulation may falter. Missing gene copies could disrupt balance. The chromosome also carries non coding genes. These produce RNA but not proteins. Some influence activity across other chromosomes.

Loss appears to alter immune regulation. Blood cell differentiation may change subtly. Heart function might also suffer indirectly. The human Y genome was fully sequenced recently. Future research may clarify mechanisms. Scientists say understanding Y loss remains urgent.

The study is published inNature Genetics Journal.