The association of ACE I/D polymorphism with the severity of COVID-19 in Iranian patients: A case-control study

BACKGROUND: Since the beginning of the COVID-19 pandemic, researchers have tried to find the reason behind the variety of the symptoms and disease severity among patients. It seems that genetic background may contribute in severity of this infection. The renin-angiotensin system (RAS) is involved in the pathogenesis of COVID-19. An Insertion/Deletion (I/D) polymorphism in the ACE1 gene may explain the genetic risk for disease severity. METHODS: We genotyped 251 COVID-19 patients: 151 patients with mild or asymptomatic disease compared with 100 patients with severe to critical illness (without any comorbidities for the disease severity). RESULTS: There was a significant association between the ACE1 DD genotype and disease severity (p-value = 1 × 10(−2); OR = 2.004, 95%CI = 1.147–3.499) and our results showed that it was inherited under recessive or codominant inheritance patterns. Also, the I allele showed a protective role against the severe form of COVID-19 disease (p-value = 1 × 10(−4)). CONCLUSION: We concluded that ACE1 DD genotype can predict the risk of severe form of COVID-19 infection in the absence of known comorbidities as disease severity risk factors. Further studies with larger sample sizes in other populations are still needed to clarify the role of ACE I/D polymorphism in SARS-CoV-2 infection severity.