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Gene

JAM2

junctional adhesion molecule 2

Summary

Cytogenetic location
21q21.3
Coordinates
Chromosome 21: 25,639,258–25,717,562 (GRCh38)
Exons
10 exons across 78.3 kb
Protein
298 amino acids
Inheritance
Autosomal recessive
Also known as
VE-JAM, JAM-B, JAMB, CD322, JAM-2
Previous symbols
C21orf43
MANE Select transcript
ENST00000480456.6NM_021219.4
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 report relevant to this gene

  • Basal Ganglia Calcification

    • Basal Ganglia Calcification, Idiopathic, 8, Autosomal RecessiveAutosomal recessive
      • 3 GenCC submitters rate it definitive or strong
    • Primary Familial Brain Calcification (All Types)

      Umbrella term covering primary familial brain calcification (bilateral striopallidodentate calcinosis), including the dominant SLC20A2, PDGFRB, PDGFB and XPR1 forms and the recessive MYORG and JAM2 forms.

      • 3 GenCC submitters rate it definitive or strong

Inheritance

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 JAM2 is laid out

  • Coding sequence
  • Untranslated region
  • Intron
  • Direction of transcription
  • Stretches short reads find hard
Chromosome 21, with a bracket where JAM2 sits. JAM2 and 4 genes near it on chromosome 21, from 25,178,410 to 26,178,409.Chromosome 2121q21.3p13p12p11.2p11.1q11.1q11.2q21.1q21.2q21.3q22.11q22.12q22.13q22.2q22.325.2 Mb25.4 Mb25.6 Mb25.8 Mb26 MbMRPL39: 25,572,145–25,607,588, reverse strandMRPL39JAM2: 25,639,258–25,717,562, forward strandJAM2ATP5PF: 25,693,623–25,735,721, reverse strandATP5PFGABPA: 25,734,570–25,772,460, forward strandGABPAAPP: 25,880,535–26,171,128, reverse strandAPPDiagram of JAM2: 10 exons on the forward strand of chromosome 21Exon 1: 25,639,258–25,639,888, 631 basesExon 2: 25,683,883–25,683,948, 66 basesExon 3: 25,689,866–25,689,973, 108 basesExon 4: 25,693,756–25,693,908, 153 basesExon 5: 25,698,677–25,698,879, 203 basesExon 6: 25,702,170–25,702,269, 100 basesExon 7: 25,705,979–25,706,086, 108 basesExon 8: 25,709,434–25,709,449, 16 basesExon 9: 25,712,340–25,712,382, 43 basesExon 10: 25,714,640–25,717,562, 2,923 bases123456789105′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 4.4 kb of the gene's 78.3 kb; 897 of those bases code for the protein.

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.
  • 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.). JAM2 gene: junctional adhesion molecule 2. Retrieved 17 October 2026, from https://dantelabs.com/genes/jam2

Vancouver

Dante Labs. JAM2 gene: junctional adhesion molecule 2 [Internet]. [cited 17 October 2026]. Available from: https://dantelabs.com/genes/jam2

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