Elderly peoplewith ApoE4, known to pose an increased risk to develop Alzheimer’s disease, are known toundergo a more severe course of COVID-19 than people who are non-carriers, and ApoE e4e4homozygotes are more likely to be COVID-positive compared to e3e3 homozygotes (Kuo et al., 2020). Here, APOE is linked to COVID-19.