IL1R1 and COVID-19: Moreover, although there is not a direct correlation with the SARS-CoV-2 infection, both the rs6734238 (located on 2q14, GA genotype) of the IL-1R gene and the rs4537545 (located on 1q21, TC genotype) of the IL-6R gene are correlated with increased serum levels of IL-6 that are correlated with COVID-19 severity and in addition represent a main target in the COVID-19 therapy (see below) [20].