Study finds thousands of non-genetic protein variants expand human proteome diversity

Researchers analyzed proteogenomic data from 29 healthy human tissues and identified over 13,900 localized protein variants, including 7,215 unique amino acid substitutions existing alongside standard reference proteins. Many of these variants arise not from DNA mutations but from translational errors, with their abundance patterns linked to population allele frequencies and specific patterns emerging under amino acid starvation in cancer cell lines.