Skip to content
Use your HSA or FSA funds

Gene

GJC2

gap junction protein gamma 2

Summary

Cytogenetic location
1q42.13
Coordinates
Chromosome 1: 228,149,930–228,159,826 (GRCh38)
Exons
2 exons across 9.9 kb
Protein
439 amino acids
Inheritance
Autosomal dominant Autosomal recessive
Also known as
CX47, CX46.6, SPG44
Previous symbols
GJA12
MANE Select transcript
ENST00000366714.3NM_020435.4
Locus type
gene with protein product
  • Very high
  • Confident
  • Low
  • Very low

Reference genomeGRCh38

Positions on gene and variant pages follow this choice, in this browser.

Curated reports relevant to this gene

  • Pelizaeus-Merzbacher Disease & Hypomyelinating Leukodystrophies

    • Pelizaeus-Merzbacher-like disease (GJC2 and others)Autosomal recessive

      A condition that closely resembles Pelizaeus-Merzbacher disease, most often caused by changes in GJC2, with early nystagmus, delayed development and later spasticity.

      • ClinGen rates the link definitive
      • 5 GenCC submitters rate it definitive or strong

  • Primary Lymphoedema & Lymphatic Malformations

    • Lymphatic Malformation 3Autosomal dominant

      Hereditary lymphoedema caused by changes in GJC2, usually starting in childhood or adolescence.

      • 2 GenCC submitters rate it definitive or strong

Broader groupings

  • Hereditary Spastic Paraplegia

    • Hereditary Spastic Paraplegia (All Types)

      One of 66 genes linked to it

      Umbrella term covering all hereditary spastic paraplegias, including SPG4 (SPAST), the most common dominant form, and SPG5A, SPG6, SPG10, SPG18, SPG30 and SPG31.

      • 1 GenCC submitter rates it definitive or strong

  • Other Inherited Leukodystrophies

    • Leukodystrophy (other and unspecified types)

      One of 80 genes linked to it

      Inherited conditions that damage or prevent the normal formation of myelin, the white matter of the brain and spinal cord. Different types follow autosomal recessive, autosomal dominant or X-linked inheritance depending on the gene involved.

      • ClinGen rates the link definitive
      • 5 GenCC submitters rate it definitive or strong
      What knowing changes

      Knowing the specific genetic cause can end a diagnostic search, guide supportive care and surveillance, show whether a specific treatment exists, and allow testing of relatives.

Inheritance

Autosomal dominant
One changed copy, from either parent, is enough. A parent who has one passes it on to each child with a one-in-two chance.
Autosomal recessive
It takes a changed copy from each parent. With one, you are a carrier and usually unaffected; when both parents are carriers, each child has a one-in-four chance of inheriting two.

How GJC2 is laid out

  • Coding sequence
  • Untranslated region
  • Intron
  • Direction of transcription
  • Known disease-causing sites
  • Stretches short reads find hard
Chromosome 1, with a bracket where GJC2 sits. GJC2 and 18 genes near it on chromosome 1, from 227,654,878 to 228,654,877.Chromosome 11q42.13p36.33p36.32p36.31p36.23p36.22p36.21p36.13p36.12p36.11p35.3p35.2p35.1p34.3p34.2p34.1p33p32.3p32.2p32.1p31.3p31.2p31.1p22.3p22.2p22.1p21.3p21.2p21.1p13.3p13.2p13.1p12p11.2p11.1q11q12q21.1q21.2q21.3q22q23.1q23.2q23.3q24.1q24.2q24.3q25.1q25.2q25.3q31.1q31.2q31.3q32.1q32.2q32.3q41q42.11q42.12q42.13q42.2q42.3q43q44227.8 Mb228 Mb228.2 Mb228.4 Mb228.6 MbZNF678: 227,542,091–227,679,669, forward strandZNF678SNAP47: 227,728,200–227,781,826, forward strandSNAP47JMJD4: 227,730,412–227,735,413, reverse strandJMJD4PRSS38: 227,815,675–227,846,478, forward strandPRSS38WNT9A: 227,918,656–227,947,939, reverse strandWNT9AWNT3A: 228,006,924–228,061,328, forward strandWNT3AARF1: 228,081,841–228,099,212, forward strandARF1C1orf35: 228,099,030–228,105,411, reverse strandC1orf35MRPL55: 228,105,949–228,109,358, reverse strandMRPL55GUK1: 228,139,962–228,148,984, forward strandGUK1GJC2: 228,149,930–228,159,826, forward strandGJC2IBA57: 228,165,777–228,182,257, forward strandIBA57OBSCN: 228,208,026–228,378,876, forward strandOBSCNTRIM11: 228,393,672–228,406,841, reverse strandTRIM11TRIM17: 228,406,860–228,416,902, reverse strandTRIM17H3-4: 228,424,845–228,425,360, reverse strandH3-4H2AC25: 228,434,777–228,457,873, reverse strandH2AC25H2BC26: 228,458,103–228,463,104, forward strandRNF187: 228,487,357–228,499,899, forward strandRNF187Diagram of GJC2: 2 exons on the forward strand of chromosome 1Exon 2: 53 known disease-causing sitesExon 1: 228,149,930–228,150,007, 78 basesExon 2: 228,157,740–228,159,826, 2,087 bases125′3′

Exons of the gene's MANE Select transcript (release v1.5), from NCBI and EMBL-EBI, on the GRCh38 reference genome.

Chromosome bands from UCSC's GRCh38 ideogram (2022-10-29).

Nearby genes from Ensembl release 116, on GRCh38.

Exons make up 2.2 kb of the gene's 9.9 kb; 1,320 of those bases code for the protein.

How a genome test reads GJC2

56

positions in GJC2 where ClinVar classes a change as pathogenic or likely pathogenic

None of them falls in a region short reads find hard.

A whole genome covers all 9.9 kb of GJC2, introns included, not only the 2.2 kb of exons.

Where this comes from

  • HGNC: the gene's symbol, name, other symbols and location.
  • MANE Select v1.5, from NCBI and EMBL-EBI: the transcript, its exons and coding sequence.
  • GenCC and ClinGen, released 2026-10-16: which conditions the gene is linked to, and how strongly.
  • The ACMG secondary findings list, SF v3.2.
  • ClinVar and the GIAB stratifications: known disease-causing sites, and the regions short reads find hard.
  • The Human Phenotype Ontology, release 2026-09-01: the traits linked to the gene. Find out more at hpo.jax.org.
  • Data release 2026.10.16-c6eea6bf.

Cite this page

APA

Dante Labs. (n.d.). GJC2 gene: gap junction protein gamma 2. Retrieved 17 October 2026, from https://dantelabs.com/genes/gjc2

Vancouver

Dante Labs. GJC2 gene: gap junction protein gamma 2 [Internet]. [cited 17 October 2026]. Available from: https://dantelabs.com/genes/gjc2

One test. A lifetime of answers.

From $449Free shipping · Results in 6–8 weeks

Get my Genome Test