CCR9 and COVID-19: A recent genome-wide association study (GWAS) has identified a genetic association between severe respiratory failure in COVID-19 hospitalized patients and the chromosome 3p21.31 [6] harboring multiple genes (LC6A20, LZTFL1, CCR9, FYCO1, CXCR6, XCR1, CCR1, CCR3, CCR2 and CCR5) that could be functionally implicated in COVID-19 [6].