Large scale sequencing efforts have identified that RPS15 mutations are found in some patients with chronic lymphocytic leukemia (CLL). This mutation may lead to changes in translation, which would result in MYC activation within B-cells. In order to determine the impact of mutants of RPS15 on CLL development, a knock-in mouse model and human cell line modeling several of the mutations will be used to determine the mutation’s impact on ribosome formation and translation.