The SRD5A3 gene provides instructions for making an enzyme called steroid 5-alpha reductase 3. This enzyme performs a chemical reaction that converts a compound called polyprenol into another compound called dolichol. Subsequently, another enzyme converts dolichol to dolichol phosphate. The production of dolichol phosphate is critical for a process called glycosylation, by which small chains of sugar molecules (oligosaccharides) are attached to proteins. Glycosylation changes proteins in ways that are important for their functions.
Dolichol phosphate is integral for the formation of the sugar chains that are attached to proteins during glycosylation. Individual sugars are added to dolichol phosphate to build the oligosaccharide chain. Once the chain is formed, it is transferred from dolichol phosphate to a specific site on the protein that needs to be glycosylated.
Health Conditions Related to Genetic Changes
SRD5A3-congenital disorder of glycosylation
More than 15 variants (also known as mutations) in the SRD5A3 gene have been found to cause SRD5A3-congenital disorder of glycosylation (SRD5A3-CDG). This condition primarily causes neurological and vision problems but can also cause other signs and symptoms.
Variants in the SRD5A3 gene generally lead to the production of abnormally small steroid 5 alpha-reductase 3 enzyme. This abnormal enzyme either has no activity or is quickly broken down. The lack of steroid 5 alpha-reductase 3 enzyme activity impairs the formation of dolichol, which also reduces dolichol phosphate production. As a result, glycosylation cannot proceed normally. The signs and symptoms of SRD5A3-CDG are likely due to impaired glycosylation of proteins that are needed for the normal function of various organs and tissues.
More About This Health Condition
Other Names for This Gene
Additional Information & Resources
Tests Listed in the Genetic Testing Registry
Scientific Articles on PubMed
Catalog of Genes and Diseases from OMIM
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