Ignorance in the sense that many parents know nothing about genotype and as such, get married to each other and just start producing children.
This na one important point, ignorance and some no even send. Those people wey dey do backyard runs wey go just dey sleep around at any hidden opportunity for dark places because dem want to prove smartness fall in this category as dem no even get time for protection both boy and the girl, as we know birds of same feathers dey fly together. So before you know am belle don enter and some don enter marriage like that even deir parents no go send to investigate certain stuff.
Stubbornness/Selfishness in the sense that some of these parents know fully well that they ain’t compatible, yet they go ahead to get married and produce children all in the name of love or with the religion mindset that a miracle will happen and the genotype of their children will miraculously change.
This na another good point. Love with the hope say things like genotype go miraculous change based on the stories wey dem don hear. I no talk say miracle no dey because miracle no dey tire Jesus but we also need to help ourselves as human beings and if God add hand for us e go become grace.
Really, na now some of us don begin know say those days wey dem go born pikin wetin few years of birth the pikin don die and dem born another one the same thing go happen dem go come say na mamiwater pikin, abiku, ogbanje etc, hmmm na genotype issue the thing go be oo.
But I believe say the awareness don dey high now about the medical compatibility of spouces on like before because the rate of sickle cell (SS) people wey I dey see around don really reduce.