The male pattern baldness is caused by genetic factors and hormones called androgens. The genetic balding pattern is acquired from both the parents.
It’s more of a gene than anything else that causes balding. The male hormone testosterone more specifically known as di-hydro- testosterone, is the reason for the hair fall out. Interestingly, the balding pattern in men is found such that it affects only the top and the front of the head and not the back.