Seroatlas · Human Serome Atlas

OCA2

P protein

Also known as: BEY, BEY1, BEY2, D15S12, EYCL, EYCL2, EYCL3, P, P_HUMAN

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
Q04671
Gene
OCA2
Ensembl
ENSG00000104044
Chromosome
15
Canonical length
838 aa
Protein class
Disease related genes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted membrane proteins, Transporters
Subcellular location
Plasma membrane,Cytosol

OverviewNCBI Gene

This gene encodes the human homolog of the mouse p (pink-eyed dilution) gene. The encoded protein is believed to be an integral membrane protein involved in small molecule transport, specifically tyrosine, which is a precursor to melanin synthesis. It is involved in mammalian pigmentation, where it may control skin color variation and act as a determinant of brown or blue eye color. Mutations in this gene result in type 2 oculocutaneous albinism. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2014]

Canonical amino-acid sequenceUniProt

838 residues, UniProt reviewed canonical sequence.

>Q04671|OCA2
     1  MHLEGRDGRR YPGAPAVELL QTSVPSGLAE LVAGKRRLPR GAGGADPSHS CPRGAAGQSS
    61  WAPAGQEFAS FLTKGRSHSS LPQMSSSRSK DSCFTENTPL LRNSLQEKGS RCIPVYHPEF
   121  ITAEESWEDS SADWERRYLL SREVSGLSAS ASSEKGDLLD SPHIRLRLSK LRRCVQWLKV
   181  MGLFAFVVLC SILFSLYPDQ GKLWQLLALS PLENYSVNLS SHVDSTLLQV DLAGALVASG
   241  PSRPGREEHI VVELTQADAL GSRWRRPQQV THNWTVYLNP RRSEHSVMSR TFEVLTRETV
   301  SISIRASLQQ TQAVPLLMAH QYLRGSVETQ VTIATAILAG VYALIIFEIV HRTLAAMLGS
   361  LAALAALAVI GDRPSLTHVV EWIDFETLAL LFGMMILVAI FSETGFFDYC AVKAYRLSRG
   421  RVWAMIIMLC LIAAVLSAFL DNVTTMLLFT PVTIRLCEVL NLDPRQVLIA EVIFTNIGGA
   481  ATAIGDPPNV IIVSNQELRK MGLDFAGFTA HMFIGICLVL LVCFPLLRLL YWNRKLYNKE
   541  PSEIVELKHE IHVWRLTAQR ISPASREETA VRRLLLGKVL ALEHLLARRL HTFHRQISQE
   601  DKNWETNIQE LQKKHRISDG ILLAKCLTVL GFVIFMFFLN SFVPGIHLDL GWIAILGAIW
   661  LLILADIHDF EIILHRVEWA TLLFFAALFV LMEALAHLHL IEYVGEQTAL LIKMVPEEQR
   721  LIAAIVLVVW VSALASSLID NIPFTATMIP VLLNLSHDPE VGLPAPPLMY ALAFGACLGG
   781  NGTLIGASAN VVCAGIAEQH GYGFSFMEFF RLGFPMMVVS CTVGMCYLLV AHVVVGWN

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against OCA2 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Other membrane
Secreted
No
Transmembrane segments
12
Mean surface accessibility (rSASA)
0.35
Highest tissue expression
28 nTPM

Expression across tissuesHPA

Tissue

  • choroid plexus: 28 nTPM
  • skin: 6 nTPM
  • blood vessel: 5.2 nTPM
  • thyroid gland: 4 nTPM
  • basal ganglia: 2.7 nTPM
  • vagina: 2.3 nTPM

Single-cell type

  • choroid plexus epithelial cells: 805 nCPM
  • melanocytes: 242 nCPM
  • ependymal cells: 184 nCPM
  • retinal pigment epithelial cells: 98 nCPM
  • other brain neurons: 46 nCPM
  • brain inhibitory neurons: 41 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • choroid plexus: 64 nTPM
  • hypothalamus: 6.5 nTPM
  • cerebral cortex: 5.4 nTPM
  • basal ganglia: 5.3 nTPM
  • white matter: 3.8 nTPM
  • midbrain: 3.6 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about OCA2.

Disease | AllUniProt

Conditions OCA2 is implicated in, by any mechanism.

Disease | GeneticClinVar

321 pathogenic / likely-pathogenic of 1,459 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on OCA2 was assayed in.

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
0.86
gnomAD pLI
0
gnomAD missense Z
-0.83
DepMap mean gene effect
-0.07
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

  • Citrate transporter-like domain
  • Diverse Ion Transporter
  • Citrate transporter

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads OCA2 as an antibody target. Whether an autoantibody or antibody against OCA2 could matter depends on whether native OCA2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

OCA2 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label OCA2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/OCA2. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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