ACE and COVID-19: Further, subgroup analyses stratified based on case proved that the ACE D allele demonstrated an association with increasing risk of COVID-19 severity (D vs. I: OR = 1.64, 95% CI = 1.01–2.66; DD vs. II: OR = 4.62, 95% CI = 2.57–8.30; DI vs. II: OR = 3.07, 95% CI = 1.75–5.38; dominant model: OR = 3.74, 95% CI = 2.15–6.50; and recessive model: OR = 1.28, 95% CI = 0.46–3.51).