1ZXM, 1ZXN, 4FM9, 4R1F715321973ENSG00000131747ENSMUSG00000020914P11388Q01320NM_001067NM_011623NP_001058NP_035753DNA topoisomerase IIα is a human enzyme encoded by the TOP2A gene.

Topoisomerase IIα relieves topological DNA stress during transcription, condenses chromosomes, and separates chromatids.

Two forms of this enzyme exist as likely products of a gene duplication event.

[citation needed] Reduced activity of this enzyme may also play a role in ataxia-telangiectasia.

[13] In Drosophila Hadlaczky et al 1988 found DNA topoisomerase II α to correlate with cell proliferation - but β did not.