Previous studies have reported that the BRAF mutation was prevalent in sporadic MSI-H and the CpG island methylator phenotype (CIMP) CRC, where MLH1 promoter hypermethylation is often seen, indicating that genomic instability in these CRCs promotes BRAF mutation, which plays a vital role in initiating tumourigenesis [42, 43]. This evidence concerns the gene MLH1 and colorectal carcinoma.