For example, in 2014, it was observed that specific intestinal microbiota are preferentially coated with high levels of immunoglobulin A (IgA) and that the specific microbes that have this high IgA coating are found to dramatically increase susceptibility to colitis (Gaboriau-Routhiau et al., 2009; Palm et al., 2014). This evidence concerns the gene CD79A and colitis.