I didn't read it (neither I think I will lol) but I heard of it. Talking about strange mangas with a friend of mine I came up with this description and yeah.

Okay so someone told me about a yaoi manga where the seme was the uke's brother and father (the seme had sex with his own mother & the uke was born from that).

Thx in advanced.

Hmmm, I’m interested at that manga too. I hope someone reply.

Is it Aniki Joutou ?

from descriptions alone i don't think that's it, any other suggestions?

Fujoshis rule!

I'm not 100% sure but could it be Yaizu Brothers ?

Yep, it was that manga (The one you both said)! Thanks!!