{"symbol":"CACNA1A","synonyms":["EA2","EIEE42","CACNL1A4","HPCA","MHP1","SCA6","CAV2.1","APCA","FHM","BI","MHP"],"name":"calcium channel, voltage-dependent, P/Q type, alpha 1A subunit","description":"Voltage-dependent calcium channels mediate the entry of calcium ions into excitable cells, and are also involved in a variety of calcium-dependent processes, including muscle contraction, hormone or neurotransmitter release, and gene expression. Calcium channels are multisubunit complexes composed of alpha-1, beta, alpha-2/delta, and gamma subunits. The channel activity is directed by the pore-forming alpha-1 subunit, whereas, the others act as auxiliary subunits regulating this activity. The distinctive properties of the calcium channel types are related primarily to the expression of a variety of alpha-1 isoforms, alpha-1A, B, C, D, E, and S. This gene encodes the alpha-1A subunit, which is predominantly expressed in neuronal tissue. Mutations in this gene are associated with 2 neurologic disorders, familial hemiplegic migraine and episodic ataxia 2. This gene also exhibits polymorphic variation due to (CAG)n-repeats. Multiple transcript variants encoding different isoforms have been found for this gene. In one set of transcript variants, the (CAG)n-repeats occur in the 3\u0027 UTR, and are not associated with any disease. But in another set of variants, an insertion extends the coding region to include the (CAG)n-repeats which encode a polyglutamine tract. Expansion of the (CAG)n-repeats from the normal 4-18 to 21-33 in the coding region is associated with spinocerebellar ataxia 6. [provided by RefSeq, Jul 2016]","ncbiEntrezGeneId":773,"ncbiEntrezGeneUrl":"http://www.ncbi.nlm.nih.gov/gene/773","proteins":[{"symbol":"CAC1A_HUMAN","href":"/api/1.0/protein/CAC1A_HUMAN"}],"hgncRootFamilies":[{"name":"Ion channels","href":"/api/1.0/gene_family/Ion+channels"}]}