US researchers have identified a gene on the X chromosome that drives inflammation in the female brain and explains the reason why women are disproportionately affected by conditions such as Alzheimer's disease and multiple sclerosis. 

The team from the University of California-Los Angeles noted that, as females have two X chromosomes, as opposed to only one in males, they get a "double dose" of inflammation, which plays a major role in ageing, Alzheimer's disease, and multiple sclerosis.