Why Women Face a Higher Risk of Multiple Sclerosis and Alzheimer’s Disease

New Delhi — Scientists in the United States have discovered a key genetic reason why women are more vulnerable to brain disorders such as Alzheimer’s disease and multiple sclerosis (MS).

Researchers from the University of California, Los Angeles (UCLA) have identified a gene on the X chromosome that triggers inflammation in the female brain — a crucial factor behind the higher prevalence of these diseases in women.

Since women have two X chromosomes, compared to one in men, they receive what researchers describe as a “double dose” of inflammation, increasing their susceptibility to brain-related disorders that are linked to ageing, such as Alzheimer’s and MS.

In experiments using a mouse model of multiple sclerosis, the team found that a gene known as Kdm6a promotes inflammation in microglia, the brain’s immune cells.

When scientists deactivated Kdm6a and its related protein, the MS-like disease and associated brain damage were significantly reduced in female mice, according to findings published in Science Translational Medicine.

“Multiple sclerosis and Alzheimer’s disease each affect women two to three times more often than men,” explained Dr. Rhonda Voskuhl, lead author of the study and director of the Multiple Sclerosis Program at UCLA Health. “Even among healthy women, nearly two-thirds experience ‘brain fog’ during menopause. These findings help explain why — and point toward new treatment strategies.”

Further testing showed that when the Kdm6a gene was ‘knocked out’ in brain immune cells, the inflammatory molecules became less active and returned to a resting state.

Researchers also reduced the protein’s activity using metformin, a common diabetes medication, and observed similarly strong results in female mice — but almost no effect in males.

“This fits with the idea that females have more of the X-linked gene to block,” said Dr. Voskuhl. “It also explains why women are more prone to diseases like multiple sclerosis and Alzheimer’s. Clinically, this suggests that women may respond differently to metformin-based treatments than men.”

With inputs from IANS