Evolutionary medicine in action: Sickle hemoglobin fuels tumor progression.

Evolutionary medicine integrates principles of evolutionary biology to understand and treat human diseases. As a classical example, positive selection of the sickle hemoglobin mutation, which confers a survival advantage against malaria in heterozygous individuals, causes sickle cell disease in homozygotes. In this issue of Immunity, Zilong Zhao et al. report a possible additional evolutionary trade-off associated with sickle hemoglobin: compromised anti-tumor immunity.