SLC6A19 and reading: For READ samples, in addition to positive correlation between ACE2-SCARB1, TMPRSS2-SLC6A19 and TMPRSS2-TMPRSS4, a moderate positive correlation between SCARB1-ACAT1 genes were also observed (Supplementary Figure S3b, p-values < 0.05 for all four; and R-values = 0.42, 0.5, 0.35 and 0.48, respectively).