Why does ALD affect males and females differently?

Why does ALD affect males and females differently?

ALD is an X-linked genetic disorder. It results from a mutated gene on the X chromosome.

Females, who have two X chromosomes, can be carriers of the disorder. One of the X chromosomes is “shut off.” That means the genes on that chromosome aren’t active.

Females usually don’t have symptoms because the “shut-off” X chromosome carries the mutated gene. Females who have symptoms usually get a milder form that develops during adulthood.

Males have only one X chromosome. The mutated X chromosome can cause more severe ALD because males lack the protective effect of the extra X chromosome.