# DNA2

Source: https://onco.cc/targets/dna2/  
OnCo record `dna2` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

DNA2 (DNA replication ATP-dependent helicase/nuclease DNA2) is an enzyme. The public catalogues list it as a DNA repair gene, and the evidence so far is association rather than a proven role.

## Summary

Key enzyme involved in DNA replication and DNA repair in nucleus and mitochondrion. Involved in Okazaki fragments processing by cleaving long flaps that escape FEN1: flaps that are longer than 27 nucleotides are coated by replication protein A complex (RPA), leading to recruit DNA2 which cleaves the flap until it is too short to bind RPA and becomes a substrate for FEN1. Also involved in 5'-end resection of DNA during double-strand break (DSB) repair: recruited by BLM and mediates the cleavage of 5'-ssDNA, while the 3'-ssDNA cleavage is prevented by the presence of RPA.

Open Targets scores its association with cancer at 0.56 (direct and indirect evidence; datatypes literature 0.93, affected pathway 0.87, genetic association 0.03).

## Fields

- Kind: Target
- Last checked: 2026-09-23
- Also known as: DNA replication helicase/nuclease 2; DNA replication ATP-dependent helicase/nuclease DNA2; KIAA0083; DNA2L
- Tags: cancer-genes-wave
- Symbol: DNA2
- Class: enzyme
- Biology: Key enzyme involved in DNA replication and DNA repair in nucleus and mitochondrion. Involved in Okazaki fragments processing by cleaving long flaps that escape FEN1: flaps that are longer than 27 nucleotides are coated by replication protein A complex (RPA), leading to recruit DNA2 which cleaves the flap until it is too short to bind RPA and becomes a substrate for FEN1. Also involved in 5'-end resection of DNA during double-strand break (DSB) repair: recruited by BLM and mediates the cleavage of 5'-ssDNA, while the 3'-ssDNA cleavage is prevented by the presence of RPA. Also involved in DNA replication checkpoint independently of Okazaki fragments processing. Possesses different enzymatic activities, such as single-stranded DNA (ssDNA)-dependent ATPase, 5'-3' helicase and endonuclease activities. While the ATPase and endonuclease activities are well-defined and play a key role in Okazaki fragments processing and DSB repair, the 5'-3' DNA helicase activity is subject to debate. Location: Nucleus; Mitochondrion (UniProt). Locus 10q21.3 (HGNC).

## 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: UniProt keyword "DNA repair". Evidence tier "association-only" is the strongest of those signals.
- Prevalence not recorded: none of the sources gives a positivity rate.

## Sources

- HGNC HGNC:2939: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:2939
- UniProt P51530: https://www.uniprot.org/uniprotkb/P51530/entry
- NCBI Gene 1763: https://www.ncbi.nlm.nih.gov/gene/1763
- Ensembl ENSG00000138346: https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000138346

## Connected records

- collections: [Open Targets Platform](https://onco.cc/collections/open-targets/)

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JSON: https://onco.cc/api/v1/entities/dna2.json