The COVID-19 pandemic gave us tremendous perspective on how wildly symptoms and outcomes can vary between patients experiencing the same infection. How can two people infected by the same pathogen have such different responses? It largely comes down to variability in genetics (the genes you inherit) and life experience (your environmental, infection, and vaccination history).

These two influences are imprinted on our cells through small molecular alterations called epigenetic changes, which shape cell identity and function by controlling whether genes are turned “on” or “off.”

Salk Institute researchers are debuting a new epigenetic catalog that reveals the distinct effects of genetic inheritance and life experience on various types of immune cells. The new cell type-specific database, published in Nature Genetics, helps explain individual differences in immune responses and may serve as the foundation for more effective and personalized therapeutics.