Zebrafish (Danio rerio) serve as a very useful model organism because they have a fast generation time, clear embryos and a well mapped genome. In this research project, the students in the Developmental Biology lab course and the students in the Freshmen Research Initiative have used these characteristics to conduct a screening of the zebrafish genome in order to identify genes that are required for development. The CRISPR/Cas9 system (a protein that creates double strand breaks at specific sites in the genome that are then repaired by the cellular machinery) was recently specialized for the use in zebrafish. However, there are usually mistakes made when repairing the break. By using this system we can create mutations at specific sites in the genome and even delete entire sections. We can then observe if the mutation has created any notable phenotypes in the developing embryo. That information can give us insight into what the genetic requirements are for development or how those mechanisms can go wrong in diseases such as cancer.