deleted this portion of LZTFL1 using a genome editor CRISPR/Cas9 in blood cell lines and found that the expression of CCR9 and SLC6A20 was affected by the locus,38 suggesting that this COVID-19 GWAS locus at chromosome locus 3p21.21 may influence different genes depending on cell type. Here, SLC6A20 is linked to COVID-19.