PTPRJ and melanoma: Mutations in the protein tyrosine phosphatase PTPRJ, 5 truncating, 3 missense, and 1 in-frame indel, were identified in 9 melanomas, 4 acral and 5 mucosal (Fig. 1B), and PTPRJ was homozygously deleted in two additional acral melanomas (Figs. 1C and 2D).