Arbel Harpak, Ph.D.

Arbel Harpak studies how genetic variation arises and how it is shaped by evolutionary processes such as natural selection. Harpak is a postdoctoral researcher in Dr. Molly Przeworski’s lab at Columbia University, working on statistical and population genetics. He holds a B.S. in both mathematics and physics and an M.S. in ecology/evolution from the Hebrew University of Jerusalem. He also holds an M.S. in statistics and a Ph.D. in biology from Stanford University, where he was advised by Dr. Jonathan Pritchard as a Stanford Center for Evolutionary and Human Genomics fellow.

At the Przeworski lab, Harpak currently studies complex (or ‘polygenic’) human traits — traits affected by thousands of genetic variants along the genome, each with a small contribution. Due to their complexity, biological mechanisms can be hard to pin down, but complex traits still lend themselves to trait prediction using Polygenic Scores — functions that aggregate input from many genetic variants. Polygenic scores can, for example, predict a person’s risk for breast cancer or coronary artery disease even in the absence of other warning signs. This approach can lead to earlier intervention for at-risk individuals. Harpak’s current work aims at elucidating the windfalls and pitfalls of polygenic trait prediction.