Consistent with the findings of Ellinghaus et al. (2020) [16], Shelton et al. (2021) reported a strong association between ABO locus on chromosome 9 and another gene-rich locus on chromosome 3 that includes Leucine zipper transcription factor-like 1 (LZTFL1) and Solute Carrier Family 6 Member 20 (SLC6A20) with the acuteness of COVID-19 using data from more than a billion participants obtained from 23andMe [22]. Here, SLC6A20 is linked to COVID-19.