Meeker et al. [76] employed germ-free Cftr KO mice treated with specified pathogen-free (SPF) fecal transplants and reported that Cftr mutations alone were sufficient to alter the fecal GI microbiome, with enrichment in the proportion of Escherichia/Shigella (>250-fold) and a depletion of Lachnoclostridium and Parabacteriodes. This result is consistent with findings in the fecal microbiome of children with CF [77]. This evidence concerns the gene CFTR and cystic fibrosis.