# STAG3

Source: https://onco.cc/targets/stag3/  
OnCo record `stag3` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

STAG3 (Cohesin subunit SA-3) is a gene. The public catalogues list it as a drug target and a biomarker, and clinical evidence ties its variants to diagnosis, prognosis or drug response. Tied to Melanoma.

## Summary

Meiosis specific component of cohesin complex. The cohesin complex is required for the cohesion of sister chromatids after DNA replication. The cohesin complex apparently forms a large proteinaceous ring within which sister chromatids can be trapped.

CIViC holds 1 clinical evidence item and 0 assertions across 1 variant, naming Vemurafenib.

## Fields

- Kind: Target
- Last checked: 2026-09-23
- Also known as: STAG3 cohesin complex component; Cohesin subunit SA-3; SA3
- Tags: cancer-genes-wave
- Symbol: STAG3
- Class: other
- Biology: Meiosis specific component of cohesin complex. The cohesin complex is required for the cohesion of sister chromatids after DNA replication. The cohesin complex apparently forms a large proteinaceous ring within which sister chromatids can be trapped. At anaphase, the complex is cleaved and dissociates from chromatin, allowing sister chromatids to segregate. The meiosis-specific cohesin complex probably replaces mitosis specific cohesin complex when it dissociates from chromatin during prophase I. Location: Nucleus; Chromosome; Chromosome, centromere (UniProt). Locus 7q22.1 (HGNC).
- Where found: Melanoma: CIViC evidence names this disease

## Notes

- Written by scripts/fetch-cancer-genes.ts from CIViC, Open Targets, IntOGen, HGNC and UniProt; the function text is UniProt's, condensed and in UK spelling. Roles: CIViC lists 1 therapies; CIViC holds 1 clinical evidence items on its variants. Evidence tier "clinical-evidence" is the strongest of those signals.
- Prevalence not recorded: none of the sources gives a positivity rate.

## Sources

- HGNC HGNC:11356: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:11356
- UniProt Q9UJ98: https://www.uniprot.org/uniprotkb/Q9UJ98/entry
- NCBI Gene 10734: https://www.ncbi.nlm.nih.gov/gene/10734
- Ensembl ENSG00000066923: https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000066923

## Connected records

- collections: [CIViC](https://onco.cc/collections/civic/)
- cancers: [Melanoma](https://onco.cc/cancers/melanoma/)

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JSON: https://onco.cc/api/v1/entities/stag3.json