What can we learn from 60,000 genome sequences? I will describe how we are leveraging the largest collection of human exomes to model the landscape of harmful genetic variations in healthy individuals. I will also discuss how we can use the previously identified variants to accurately estimate properties of the unobserved variants that exist in the general population. Our linear program estimators have strong mathematical guarantees. This model of rare, unobserved variants provides a roadmap for future sequencing projects, such as the Precision Medicine Initiative.