sparky_1966 t1_ja8p8n1 wrote on February 27, 2023 at 5:52 PM

Reply to comment by fingawkward in Is there a genetic disease where the heterozygote has more severe disease symptoms than the homozygote? by Altranite-

You are correct, heterozygous provides some protection from malaria and homozygous causes sickle cell. The heterozygotes are still not normal and are less healthy than normal people, but the negative pressure from malaria is strong enough that it's a net gain.