Using the expression of 17 key genes (messenger RNAs) it is now possible to distinguish primary and metastatic cutaneous melanoma, which is the most common type of skin cancer. While 11 of the 17 genes have already been reported by other studies for cutaneous melanoma, it is for the first time that the potential role of remaining six genomic signatures in classifying samples as either primary or metastatic skin cutaneous cancer has been made. The 17 genomic signatures, which were identified by a team led by Prof. Gajendra P.S. Raghava from the Indraprastha Institute of Information Technology (IIIT), New Delhi, have high accuracy -- over 89% -- in discriminating metastatic from primary skin melanoma. These signatures also have high sensitivity (in case tumour is metastatic), and high specificity (in case the tumour is primary). The results were published in the journal Scientific Reports.