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LOC108663985 calcium voltage-gated channel subunit alpha1 A repeat instability region [ Homo sapiens (human) ]

Gene ID: 108663985, updated on 10-Dec-2019


Gene symbol
Gene description
calcium voltage-gated channel subunit alpha1 A repeat instability region
Gene type
biological region
Feature type(s)
misc_feature: repeat_instability_region
RefSeq status
Homo sapiens
Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo
This biological region is found within an exon of the calcium voltage-gated channel subunit alpha1 A (CACNA1A) gene on the p arm of chromosome 19, and contains a CAG trinucleotide repeat. This trinucleotide repeat is found in the 3' coding region of some transcript variants of the CACNA1A gene, while it is in the 3' untranslated region of other variants. For those variants containing the trinucleotide repeat in the coding region, expansions of this repeat result in an elongated polyglutamine tract in the encoded protein. Expansions are known to be a cause of spinocerebellar ataxia type 6 (SCA6), an autosomal dominant progressive disorder. There is allelic variation at this locus, with up to 19 CAG repeats for most non-pathogenic alleles. Individuals with expanded alleles of 20-33 CAG repeats typically develop symptoms at some point during their lifetime. [provided by RefSeq, Jan 2017]

Genomic context

See LOC108663985 in Genome Data Viewer
Annotation release Status Assembly Chr Location
109.20191205 current GRCh38.p13 (GCF_000001405.39) 19 NC_000019.10 (13207859..13207898)

Chromosome 19 - NC_000019.10Genomic Context describing neighboring genes Neighboring gene Sharpr-MPRA regulatory region 13602 Neighboring gene uncharacterized LOC107985288 Neighboring gene calcium voltage-gated channel subunit alpha1 A Neighboring gene NFE2L2 motif-containing MPRA enhancer 68 Neighboring gene uncharacterized LOC105372283

Genomic regions, transcripts, and products

General gene information

Other Names

  • CACNA1A repeat instability region
  • SCA6 repeat instability region
  • spinocerebellar ataxia type 6 repeat instability region

NCBI Reference Sequences (RefSeq)

RefSeqs maintained independently of Annotated Genomes

These reference sequences exist independently of genome builds. Explain

These reference sequences are curated independently of the genome annotation cycle, so their versions may not match the RefSeq versions in the current genome build. Identify version mismatches by comparing the version of the RefSeq in this section to the one reported in Genomic regions, transcripts, and products above.


  1. NG_051543.1 

    GenBank, FASTA, Sequence Viewer (Graphics)

RefSeqs of Annotated Genomes: Homo sapiens Updated Annotation Release 109.

The following sections contain reference sequences that belong to a specific genome build. Explain

Reference GRCh38.p13 Primary Assembly


  1. NC_000019.10 Reference GRCh38.p13 Primary Assembly

    GenBank, FASTA, Sequence Viewer (Graphics)
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