In this patient the BRAF V600E mutation was identified in sorted CD146+/MCAM+/CD45− cells, whilst the mutation was not identified in sorted leukocytes (MCAM−/MCSP−/CD45+ cells) from the same specimen (Fig. S3), confirming that MCAM+/MCSP+ cells identified by FCM indeed represent true melanoma cells. The gene discussed is PTPRC; the disease is melanoma.