MMP20 and amelogenesis imperfecta: There are reports that mutations and SNPs of AMELX (Amelogenin X-Linked), AMBN (Ameloblastin), ENAM (Enamelin), TUFT1 (Tuftelin 1), FAM83H (Family With Sequence Similarity 83 Member H), and MMP20 (Matrix Metallopeptidase 20) genes, cause different nonsyndromic enamel conditions such as amelogenesis imperfecta (AI) [9,10,11,12].