Unfortunately, MPB can appear without a direct family history. There are many genes for hair loss, and it is possible for generations to be skipped. Best of luck with your hair.
Hair loss without family history of MPB
It is possible to experience hair loss from male pattern alopecia without having close relatives with the condition. That is, because hair loss can be inherited from either side of the family, and it may skip a generation. But are you sure that it is MPB? The hallmark of AGA is miniaturization in a pattern distribution.
Bernardino A. Arocha, MD
Male Pattern Balding Inheritance
MPB is inherited from both parents and is not just one gene. Your story is not uncommon, you may have inherited a lot of balding genes from both sides rather than getting the good genes for hair.
No family history of hair loss
Sometimes, the genes that cause hair loss skip generations. In my 25 years in practice, I hear this history with great frequency.