Protection afforded by sickle-cell trait against subtertian malarial infection.

Allison was the first to connect a hereditary disease (sickle cell disease) to an infectious disease (malaria). He proved that heterozygous and homozygous individuals to the sickle cell trait or disease respectively show a resistance to malarial illness which allows them to survive while others die. The sickle cell individuals then survive to puberty, reproduce and pass down their ‘beneficial’ trait. Digital facsimile from PubMedCentral at this link.

In 1956 Allison published a semi-popular version of this research as "Sickle cells and evolution," Scientific American, 195 (1956) 87-94.

(Thanks to Juan Weiss for this reference and its interpretation.)

In 2014 Allison was interviewed concerning his sickle cell research in this video from hhmi biointeractive: