I am a statistical and population geneticist interested in characterizing the relationship between DNA sequence variation and susceptibility to complex diseases. The goal with this approach is to identify causal pathways and gene targets that are therapeutically actionable. To identify these leads, my lab constructs statistical methods grounded in quantitative genetics and population biology, applying them to genetic data collected across whole genomes. Over my career, the statistical pipelines that I have developed and applied to the analysis of genetic data in humans have uncovered thousands of loci for complex traits, including type 2 diabetes, heart disease, and liver disease. In addition, my lab has expertise on mapping genetic variation associated with molecular phenotypes including gene expression, accessible chromatin, and methylation state across tissues and cell models, including footprintQTLs (fpQTLs). I have led the application of Mendelian randomization (MR) to evaluate causal hypotheses between biomarkers and cardiometabolic endpoints, including evidence against a protective role for increasing high-density lipoprotein cholesterol in heart disease, but as a putative risk factor for breast cancer. My group also studies pleiotropy, applying methods for the analysis of auto-immune disease and cardiometabolic traits, as well as at scale, i.e., our large-scale genome- and phenome-wide association scan in >650k participants in the Million Veteran Program. We also create methods in population genomics, which include characterization of mutation rates and studies of natural selection in human populations.
My expertise includes statistical genetics, genetic epidemiology, bioinformatics, computational biology, and data science with special focus on data collections in humans. My contributions in complex trait genetic studies, QTL mapping for metabolic traits, expertise in causal inference studies and multi-trait analysis, demonstrate empirically my capability to successfully create analytical workflows with impact. I have extensive experience advancing human genetic studies as a leader in a “Team Science” capacity (e.g., DIAGRAM, DIAMANTE, T2D-GO, MVP, HPAP-T2D, T2D-AMP, T2DGGI), including those focused on data aggregation (e.g., PanKbase), working productively in this type of collaborative capacity.
Advised by Drs. Jonathan Pritchard (now at Stanford) and Nancy Cox (now at Vanderbilt), in 2006 I received my Ph.D. in Human Genetics at the University of Chicago. As a post-doctoral research fellow from 2006-2009, I worked with Drs. David Altshuler (now at Vertex Pharmaceuticals) and Mark Daly at the Center of Human Genetics Research at Massachusetts General Hospital. From 2009 until September of 2011, I remained at the Broad Institute of Harvard and MIT as a Research Scientist. In September of 2011, I joined the faculty ranks of the Departments of Systems Pharmacology and Translational Therapeutics and Genetics at the University of Pennsylvania Perelman School of Medicine as an Assistant Professor, becoming an Associate Professor (with tenure) in 2017, and made Full Professor in 2025. I am also appointed at the VA as a Health Science Research Specialist (1/8ths effort, to be 6/8th in April, 2026). I am a member of the Institute for Translational Medicine and Therapeutics and the Institute for Biomedical Informatics. I also serve as chair of the Genomic and Computational Biology (GCB) Graduate group here at Penn.