However, they found that after inducing chronic colitis in mice using DSS or AOM/DSS multiple times, the expression of DDR genes MLH1, Anapc1, and ERCC4 mRNA significantly decreased, suggesting that the downregulation of ERCC4 expression after chronic colitis may be related to the occurrence of early tumors, which warrants further exploration (130). The gene discussed is ERCC4; the disease is infectious otitis media.