By contrast, Bacillota members, including Lachnospiraceae, Faecalibacterium spp., Streptococcus spp., and Intestinibacter bartlettii, have been associated with ICI colitis and other irAEs in independent cohorts of anti-CTLA-4, anti-PD-1, or combination ICI-treated metastatic melanoma patients (Andrews et al., 2021; Chaput et al., 2017; McCulloch et al., 2022). This evidence concerns the gene PDCD1 and metastatic melanoma.