Closer inspection of the overlap between the 19 and 33 genes used to distinguish the primary melanoma and melanoma metastases data sets revealed nine genes in common: ACTN1, ARPC1B, IMP3, KIAA0553, MGC3731, MTCP1, RAC1, RALBP1, and SDFR1. The gene discussed is NPTN; the disease is melanoma.