Cancer is a genetic disease that involves the accumulation of somatic mutations. Comprehensive understanding of the mutations that cause cancer and their functional effects is a critical step towards: a) global understanding of cancer development and tumor phenotypes, b) sub-classification of cancer based on mutational signatures, and c) developing targeted therapies based on mutations in specific tumors.Recent advances in high-throughput genomic technologies provide an unprecedented opportunity to systematically interrogate the cancer genetic landscape. However, although ample genomic sequences are becoming available, so far these have only provided limited information concerning the complexity of the cancer genome. Furthermore, our understanding of the functional effects of identified mutations is hampered by the difficulty in comprehensively assessing their biological and biochemical effects in a physiological manner.I propose to overcome this major challenge in our understanding of cancer genomics by integrating functional and genetic techniques using melanoma as an example. I propose pioneering high-throughput applications of somatic cell knockout technologies to evaluate newly discovered mutations. The tools developed by this proposal will make it possible to decisively determine the function(s) of proteins that are intimately linked to the pathogenesis of cancer. Funding for this project will enable us to demonstrate the feasibility of initiating a larger scale approach to the ongoing identification of a dynamic and evolving cancer interactome. Furthermore, we will analyze 300 melanoma whole exomes, the largest melanoma dataset to date, to: (i) identify new targetable mutations and (ii) determine the roles of synonymous mutations, which have rarely been studied in cancer. The proposed research will reveal the mechanisms underlying melanoma tumorgenesis, which will in turn generate insights to aid the treatment of melanoma patients.