Biology

Your DNA breaks all day, every day

Constantly. Every cell in your body takes something on the order of 10,000 to 100,000 chemical hits to its DNA every day, from sunlight, from oxygen, and from the molecule simply coming apart on its own. You stay alive because repair enzymes find and rewrite the damaged letters faster than the damage arrives.

Sources & further reading

The Royal Swedish Academy of Sciences / NobelPrize.orgPress release: The Nobel Prize in Chemistry 2015The official Nobel announcement for the three scientists who worked out how cells fix their own DNA, and the ground-truth source for the claim that DNA falls apart every day.The Royal Swedish Academy of Sciences / NobelPrize.orgDNA repair, providing chemical stability for life. Popular science background, The Nobel Prize in Chemistry 2015The Nobel committee's plain-language explainer of the same prize, with the step-by-step of how a sunlight lesion gets cut out and patched.Nature (Nature Publishing Group)Instability and decay of the primary structure of DNAThe review by the scientist who first realised DNA is chemically unstable, laying out exactly how the molecule falls apart on its own.New England Journal of Medicine (Massachusetts Medical Society)DNA Damage, Aging, and CancerA leading medical-journal review that puts a number on the daily damage: tens of thousands of chemical injuries in every cell, every day.GeneReviews, University of Washington, Seattle (NCBI Bookshelf, National Library of Medicine)Xeroderma PigmentosumThe clinical reference on the rare inherited condition where the DNA sunlight-repair crew is missing, showing what happens to a body when that repair stops.Clinical Cancer Research (American Association for Cancer Research) / PubMed, National Library of Medicine (NIH)FDA Approval Summary: Olaparib Monotherapy in Patients with Deleterious Germline BRCA-Mutated Advanced Ovarian Cancer Treated with Three or More Lines of ChemotherapyThe FDA's own published summary of the first approved cancer drug that works by attacking a tumour's already-damaged DNA repair system.Nature (Nature Publishing Group)Reassembly of shattered chromosomes in Deinococcus radioduransThe study showing a soil bacterium whose genome is blown into hundreds of pieces can put all 3.28 million letters back in the right order.