In addition, IRF-6 (which plays a role in promoting epithelial–mesenchymal transition in lip and palatal fusion) was found to be hypermethylated, and hypermethylated IRF-6 increased the risks of cleft lip and palate (CLP) rather than other types of orofacial clefts, as shown by OR of CLP: 6.0, OR of CL/P: 4.67, and OR of CLO: 3.6 [21]. This evidence concerns the gene IRF6 and orofacial cleft.