X-Linked Gene Drives Brain Inflammation in Women

For decades, clinicians have noted that women face greater risks of multiple sclerosis (MS) and Alzheimer’s disease (AD)—and report higher rates of cognitive symptoms during menopause. These sex-specific differences have resisted easy explanation. Hormones such as estrogen clearly play a role, but their decline does not fully account for why female brains appear more vulnerable to neuroinflammatory and neurodegenerative processes.

Now, researchers at UCLA Health have pinpointed a second, genetic layer to this disparity: a gene on the X chromosome that amplifies inflammatory signaling in the brain’s immune cells.

The new study, published in Science Translational Medicine , identifies Kdm6a as a master regulator of microglial activation. Females, who carry two X chromosomes rat