He has made major inroads into the genetic analysis of patterning and morphogenesis of vertebrate embryos, using zebrafish as a model organism. He has analyzed the function of numerous genes that control the cellular mechanisms and signal transduction pathways underlying the patterning and morphogenesis of the vertebrate head. More recently Dr. Schier has begun to elucidate some of the mechanisms underlying the development of left-right asymmetry in the vertebrate body and in individual organs.