Break induced replication (BIR) is a process by which double-strand breaks in DNA incurred from environmental damages and normal cellular processes can be repaired. My research explores how vulnerabilities of and perturbations to this process can result in mutations and genomic rearrangements. Further, I have developed a method to computationally identify these mutagenic consequences of BIR repair processes in human genomic sequencing data, tying BIR repair to variation in normal cells and mutagenesis in cancer.