# U2AF1

Source: https://onco.cc/targets/u2af1/  
OnCo record `u2af1` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

U2AF1 (Splicing factor U2AF 35 kDa subunit) is a gene that drives cell growth when it is altered. The public catalogues list it as an oncogene driver and a biomarker, and clinical evidence ties its variants to diagnosis, prognosis or drug response. Tied to Myeloproliferative neoplasms, Leukaemia, Lung cancer and 5 more.

## Summary

Plays a critical role in both constitutive and enhancer-dependent splicing by mediating protein-protein interactions and protein-RNA interactions required for accurate 3'-splice site selection. Recruits U2 snRNP to the branch point. Directly mediates interactions between U2AF2 and proteins bound to the enhancers and thus may function as a bridge between U2AF2 and the enhancer complex to recruit it to the adjacent intron.

CIViC holds 9 clinical evidence items and 0 assertions across 4 variants. Open Targets scores its association with cancer at 0.76 (direct and indirect evidence; datatypes affected pathway 0.61, literature 0.93, genetic association 0.00, somatic mutation 0.97, animal model 0.53). IntOGen calls it a driver in 15 cohorts (15 activating, 0 loss-of-function), covering Acute Myeloid Leukaemia, Cholangiocarcinoma, Lung Adenocarcinoma, Non-Small Cell Lung Cancer, Pancreatic Adenocarcinoma, Prostate Adenocarcinoma and others.

## Fields

- Kind: Target
- Last checked: 2026-09-23
- Also known as: U2 small nuclear RNA auxiliary factor 1; Splicing factor U2AF 35 kDa subunit; U2AF35; RNU2AF1; U2AFBP
- Tags: cancer-genes-wave
- Symbol: U2AF1
- Class: oncogene
- Biology: Plays a critical role in both constitutive and enhancer-dependent splicing by mediating protein-protein interactions and protein-RNA interactions required for accurate 3'-splice site selection. Recruits U2 snRNP to the branch point. Directly mediates interactions between U2AF2 and proteins bound to the enhancers and thus may function as a bridge between U2AF2 and the enhancer complex to recruit it to the adjacent intron. Location: Nucleus; Nucleus speckle (UniProt). Locus 21q22.3 (HGNC).
- Where found: Myeloproliferative neoplasms: Open Targets association 0.70 with myeloproliferative neoplasm (MONDO_0020076); Leukaemia: Open Targets association 0.70 with leukaemia (MONDO_0005059); Lung cancer: Open Targets association 0.64 with lung cancer (MONDO_0008903); Pancreatic ductal adenocarcinoma: IntOGen driver in 4 cohorts (PAAD); Myelodysplastic syndromes / neoplasms: CIViC evidence names this disease; Prostate cancer: IntOGen driver in 1 cohort (PRAD)

## 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: IntOGen calls it an activating (Act) driver in 15 cohorts; CIViC holds 9 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.
- Diseases the sources name that have no OnCo cancer page yet, so they are not linked: Myelofibrosis.

## Sources

- HGNC HGNC:12453: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:12453
- UniProt Q01081: https://www.uniprot.org/uniprotkb/Q01081/entry
- NCBI Gene 7307: https://www.ncbi.nlm.nih.gov/gene/7307
- Ensembl ENSG00000160201: https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000160201

## Connected records

- collections: [CIViC](https://onco.cc/collections/civic/), [IntOGen](https://onco.cc/collections/intogen/), [Open Targets Platform](https://onco.cc/collections/open-targets/)
- cancers: [Endometrial cancer](https://onco.cc/cancers/endometrial/), [Gastric & gastro-oesophageal junction cancer](https://onco.cc/cancers/gastric/), [Leukaemia (all types)](https://onco.cc/cancers/leukaemia/), [Lung cancer (all types)](https://onco.cc/cancers/lung-cancer/), [Myelodysplastic syndromes / neoplasms (MDS)](https://onco.cc/cancers/mds/), [Myeloproliferative neoplasms (PV, ET, myelofibrosis)](https://onco.cc/cancers/myeloproliferative-neoplasms/), [Pancreatic ductal adenocarcinoma](https://onco.cc/cancers/pancreatic/), [Prostate cancer](https://onco.cc/cancers/prostate/)
- pathways: [RNA splicing](https://onco.cc/pathways/rna-splicing/)

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JSON: https://onco.cc/api/v1/entities/u2af1.json