Mostbiological traits have a strong genetic, or heritable, component. Understanding how genetic variation influences these phenotypes will be important for understanding common, heritable diseases like autism.However, the genetic architecture controlling most biological traits is incredibly complex - hundreds of interacting genes and variants combine in unknown ways to create phenotype.The McGrath lab is interested in using fundamentalmechanistic studies inC. elegansto identify, predict, and understand how genetic variation impacts the function of the nervous system.We are studying laboratory adapted strains and harnessing directed evolution experiments to understand how genetic changes affect development, reproduction, and lifespan. We combine quantitative genetics, CRISPR/Cas9, genomics, and computational approaches to address these questions.We believe this work will lead to insights into evolution, multigenic disease, and systems biology.