Dad bald, 3 brothers bald 1 brother not bald, what are my chances?

Dad is bald at 68 but I he had most of his hair at 30 I think Eldest brother at 31 is balding at the back but barely any hair loss, don’t think his temples are bad but would never notice Next brother at 28 shaved his head Next one at 25 shaved his head Next one at 22 has significant hair loss noticeable when he puts his hair up What are my chances? It is supposed to be a 50/50 on the mom&#

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