Scientists have found a genetic mutation in melanoma skin cancer cells that increases the disease’s severity but which could also be a target for new drugs against the killer illness.They studied cells from patients with early and advanced melanoma tumors and found extra copies of a gene called MITF.About 10 percent of primary tumors and 21 percent of metastatic tumors -- those that had spread beyond the original site -- had up to 13 extra copies of the gene.
