An individual homozygous for the recessive sickle hemoglobin, HgbS, has a short expectancy of life, whereas the life expectancy of the standard hemoglobin (HgbA) homozygote and also the heterozygote is normal (though heterozygote individuals will suffer periodic problems).
Un individuo homocigoto recesivo para a hemoglobina falciforme, HgbS, ten unha curta expectativa de vida, mentres que a expectativa de vida dos homocigotos para a hemoglobina "normal" (HgbA) e a dos heterocigotos é a normal (aínda que os individuos heterocigotos sofren problemas periódicos).