Health Topics
Official websites use .gov
A
.gov website belongs to an official government
organization in the United States.
Secure .gov websites use HTTPS
A
lock (
) or https:// means you’ve safely connected to
the .gov website. Share sensitive information only on official,
secure websites.
Normal Function
The FAM20A gene provides instructions for making a protein that is found in cells throughout the body. The FAM20A protein plays a role in the process of mineralization, in which minerals such as calcium and phosphorus are deposited in developing bones and teeth. Mineralization is critical for the formation of strong and rigid bones. It is also involved in building tooth enamel, which is the hard, white material that forms the protective outer layer of each tooth. Enamel strengthens teeth so they can withstand chewing and grinding. The FAM20A protein also plays a role in regulating the levels of calcium in the kidneys.
Health Conditions Related to Genetic Changes
Amelogenesis imperfecta
Variants (also called mutations) in the FAM20A gene have been found to cause a disorder called amelogenesis imperfecta. In people with this disorder, tooth enamel does not form properly and is very thin. As a result, people with amelogenesis imperfecta may have teeth that are unusually small, discolored, pitted, or grooved. When this condition is caused by FAM20A gene variants, it is inherited in an autosomal recessive pattern, which means that both copies of the gene in each cell are altered. Some people with amelogenesis imperfecta caused by FAM20A gene variants also develop calcium deposits in the kidneys (nephrocalcinosis) later in life. Because the kidneys can be affected, this form of amelogenesis imperfecta is sometimes called enamel-renal syndrome. People with enamel-renal syndrome also tend to have overgrowth of the gums (gingival hyperplasia), missing teeth, and short tooth roots.
Most of the FAM20A gene variants that cause amelogenesis imperfecta cause cells to produce altered versions of the FAM20A protein that do not function properly. Without functional FAM20A proteins, the normal development of tooth enamel is disrupted. As a result, affected individuals have the thin enamel and the fragile and discolored teeth that are characteristic of amelogenesis imperfecta.
More About This Health ConditionOther Names for This Gene
- AI1G
- AIGFS
- FP2747
Additional Information & Resources
Tests Listed in the Genetic Testing Registry
Scientific Articles on PubMed
Catalog of Genes and Diseases from OMIM
References
- de la Dure-Molla M, Quentric M, Yamaguti PM, Acevedo AC, Mighell AJ, Vikkula M, Huckert M, Berdal A, Bloch-Zupan A. Pathognomonic oral profile of Enamel Renal Syndrome (ERS) caused by recessive FAM20A mutations. Orphanet J Rare Dis. 2014 Jun 14;9:84. doi: 10.1186/1750-1172-9-84. Citation on PubMed
- Ding JN, Yu M, Liu HC, Sun K, Wang J, Xu XL, Liu Y, Han D. FAM20A-Associated Amelogenesis Imperfecta: Gene Variants with Functional Verification and Histological Features. Chin J Dent Res. 2024 Mar 28;27(1):53-63. doi: 10.3290/j.cjdr.b5136761. Citation on PubMed
- Nitayavardhana I, Theerapanon T, Srichomthong C, Piwluang S, Wichadakul D, Porntaveetus T, Shotelersuk V. Four novel mutations of FAM20A in amelogenesis imperfecta type IG and review of literature for its genotype and phenotype spectra. Mol Genet Genomics. 2020 Jul;295(4):923-931. doi: 10.1007/s00438-020-01668-8. Epub 2020 Apr 3. Citation on PubMed
- Smith CEL, Poulter JA, Antanaviciute A, Kirkham J, Brookes SJ, Inglehearn CF, Mighell AJ. Amelogenesis Imperfecta; Genes, Proteins, and Pathways. Front Physiol. 2017 Jun 26;8:435. doi: 10.3389/fphys.2017.00435. eCollection 2017. Citation on PubMed
The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.