President Obama has promised to support a bold future for medicine where diagnostic testing and treatments aren’t just what’s best for most people – they’re what’s best for you.

This “precision medicine” takes individual variations in our genes and environments into account. Getting there will require genetic and health data from as many people as possible to uncover the relationship between genetic differences and medical outcomes.

This is why Obama’s Precision Medicine Initiative (PMI) includes the creation of a million-person research cohort. Participants will provide blood and urine samples, share information from their electronic health records and answer questions about health and lifestyle. The hope is that this trove of data will reveal the genetic underpinnings for a variety of diseases, leading to personalized diagnostics and treatments.