Each year, over 400,000 people are diagnosed with multiple myeloma, an incurable form of lymphoma responsible for 80,000 deaths annually. Multiple myeloma is different from other lymphomas because it affects plasma cells--the cells responsible for producing antibodies, which are the proteins that allow our immune systems to identify and respond to pathogens and other dangers. Several important genetic processes allow plasma cells to produce a nearly unlimited variety of antibodies from a limited number of genes. One of these processes, called V(D)J recombination, selects two gene segments from large repertoires of antibody-encoding genes and fuses them into a single gene. Because this gene product is unique and shared by all descendants of the initially-rearranged cell, it can be used as a marker to identify a single plasma cell lineage, or “clone.” For my project, I am designing a quantitative Polymerase Chain Reaction assay to quantify the presence of a single clone within a myeloma tumor. By tracking a single clone throughout myeloma progression, we can more accurately determine whether previously-characterized genetic changes that arise throughout myeloma progression are due to novel mutations in the original dominant clone or to a new clone outcompeting the original by natural selection. Through facilitating this type of research, this assay will help researchers rapidly detect clonal evolution and will help clinicians predict patient outcomes more accurately.