system
Given the following post, respond as if you're commenting on Reddit:
human
Is baldness in males really passed down from your mother's father?

I've always heard this is true. Is it? And if so, is it a hard and fast rule, or is it a mere propensity or increased likelihood of baldness?
gpt
One type of male pattern baldness is sex-linked, affecting the X chromosome. Females have two X chromosomes and males have an X and a Y chromosome. If mother's father had male pattern baldness, then your mother has at least one copy of a defective X chromosome, giving you a 50% chance of being bald. If your father's father had male pattern baldness, the Y chromosome that gets passed to your father is unaffected. This is only for male pattern baldness, but it accounts for most of the balding that occurs.