Bioinformatics Database
AMELX: Amelogenin X-linked
Cellular Process
Enamel formation
Gene Name
AMELX: Amelogenin X-linked
Gene ID
265
Gene Sequence
General Description
This gene encodes a member of the amelogenin family of extracellular matrix proteins. Amelogenins are involved in biomineralization during tooth enamel development. Mutations in this gene cause X-linked amelogenesis imperfecta. Alternative splicing results in multiple transcript variants encoding different isoforms.
Alternative titles; symbols
ALGN AMG AMGL
Chromosome
Chromosome X
Cytogenetic location
Xp22.2
Encoded Protein
Amelogenin, X isoform isoform 1 precursor
Function of the protein in oral and tooth development
Enamel, the outermost covering of the teeth and the hardest tissue in the body, contains both enamelin (606585) and amelogenin. Amelogenins are highly conserved proteins secreted by ameloblasts, and constitute 90% of the enamel organic matrix (Gibson et al., 2001).
Dental and Oral Diseases
Amelogenesis imperfecta, type 1E
(OMIM ID: 300391)
Protein Sequence
>NP_001133.1 amelogenin, X isoform isoform 1 precursor [Homo sapiens]
MGTWILFACLLGAAFAMPLPPHPGHPGYINFSYEVLTPLKWYQSIRPPYPSYGYEPMGGWLHHQIIPVLS
QQHPPTHTLQPHHHIPVVPAQQPVIPQQPMMPVPGQHSMTPIQHHQPNLPPPAQQPYQPQPVQPQPHQPM
QPQPPVHPMQPLPPQPPLPPMFPMQPLPPMLPDLTLEAWPSTDKTKREEVD
Mutations
1-BP DEL, 541C: Kindelan et al. (2000) identified a cytosine deletion in exon 6 at codon 119 of the AMELX gene. The deletion resulted in a frameshift mutation, introducing a premature stop signal at codon 126.
1-BP DEL, 420C: Greene et al. (2002) identified a deletion of cytosine at position 446 of the AMELX gene. This frameshift mutation deletes part of the coding region for the repetitive portion of amelogenin as well as the hydrophilic tail, replacing them with a 47-amino acid segment containing 9 cysteine residues.
TRP4SER; MET1THR: Kim et al. (2004).
53-KB DEL; 96-KB DEL: Hu et al. (2012).
PRO70THR: Collier et al. (1997) identified a 208C-A mutation in exon 6 of the amelogenin gene resulting in a pro21-to-thr substitution. Affected males have enamel that is mottled brown or with a ground-glass appearance and is described as hypomature.
GLU191TER; THR51ILE; 1-BP DEL, 473C: Lench & Winter (1995).
9-BP DEL: Lagerstrom-Fermer et al. (1995) described a 9-bp deletion in exon 2 of the ALGN gene, causing X-linked hypoplastic amelogenesis imperfecta.
5-KB DEL: Lagerstrom-Fermer et al. (1995).
1-BP DEL, 155C: In a family with X-linked amelogenesis imperfecta (AI1E; 301200), Aldred et al. (1992) found that the disorder was associated with deletion of one cytosine in exon 5 of the AMELX gene. The effect of the deletion was to alter the reading frame and to introduce an inappropriate TGA stop codon (an opal mutation) into the exonic sequence immediately 3-prime of the deletion.
Related Literature
Gibson et al., (2001): https://doi.org/10.1074/jbc.M104624200
Lagerström-Fermér et al., (1995): https://doi.org/10.1016/0888-7543(95)80097-6
Kindelan et al., (2000): https://doi.org/10.1177/00220345000790120901
Kim et al., (2004): https://doi.org/10.1177/154405910408300505
Hu et al., (2012): https://doi.org/10.1371/journal.pone.0052052
Greene et al., (2002): https://doi.org/10.1016/s0003-9969(01)00111-x
Collier et al., (1997): https://doi.org/10.1016/s0003-9969(96)00099-4
Lench & Winter, (1995): https://doi.org/10.1002/humu.1380050310
Aldred et al., (1992):https://doi.org/10.1007/BF00220469
