An earlier bioinformatics study on the potential genes associated with COVID-19 and comorbidities (hypertension, diabetes mellitus and coronary artery disease) found that there were eleven shared genes (TLR4, NLRP3, MBL2, IL6, IL1RN, IL1B, CX3CR1, CCR5, AGT, ACE and F2) [42]. Here, CCR5 is linked to diabetes mellitus.