What is PDRN (salmon DNA) in skincare?

PDRN is polydeoxyribonucleotide, a repair-signalling ingredient made from purified, fragmented salmon or trout DNA. In topical serums it is used to support hydration and a smoother, plumper, more even-looking complexion. It is the active behind the 'pink peptide' and salmon-DNA serums trending in K-beauty, and it layers comfortably under moisturiser in both morning and evening routines.