DNAreparaatiossa

DNAreparaatio, or DNA repair, is a fundamental cellular process that maintains the integrity of the genome. Cells constantly encounter DNA damage from various sources, including environmental factors like ultraviolet radiation and chemical mutagens, as well as internal metabolic byproducts. If left unrepaired, this damage can lead to mutations, chromosomal abnormalities, and ultimately, cell death or disease, such as cancer.

There are several major DNA repair pathways, each specialized to handle different types of DNA lesions. Base excision repair (BER) corrects small, non-helix-distorting lesions, such as oxidized or alkylated bases. Nucleotide excision repair (NER) removes bulky, helix-distorting adducts, like those caused by UV radiation. Mismatch repair (MMR) corrects errors that occur during DNA replication, such as misincorporated bases. Double-strand breaks, one of the most lethal types of DNA damage, are repaired by homologous recombination (HR) or non-homologous end joining (NHEJ).

These repair mechanisms are crucial for life. Defects in DNA repair pathways can result in genetic instability and are often associated with increased susceptibility to cancer and other genetic disorders. The study of DNA repair is vital for understanding disease pathogenesis and developing therapeutic strategies.