Castle Biosciences has launched DecisionDx-CMSeq test that uses next-generation sequencing (NGS) to identify somatic mutations in genes relevant to cutaneous melanoma (CM). The test will complement the company’s DecisionDx-Melanoma GEP test that predicts individual risk of recurrence in patients with melanoma. DecisionDx-CMSeq evaluates DNA mutations in the BRAF and NRAS genes and can be ordered in conjunction with the DecisionDx-Melanoma GEP test, or as a standalone. BRAF is found in approximately 40 to 50% of CM tumors. The DecisionDx-CMSeq test analyzes mutations in exon 15 of BRAF, where the most common and clinically actionable mutations occur. And roughly 20% of melanoma tumors exhibit NRAS mutations. The test identifies mutations affecting codons G12, G13, and Q61 of the NRAS gene.