title: Stable association of a pigmentation allele with an oncogene: nonhybrid melanomas in Xiphophorus variatus.
abstract: Sex-linked genes in several species of the fish genus Xiphophorus cause macromelanophore pigmentation patterns on the flanks of the fish. Some, but not all, of these patterns can develop into melanomas. The tumorigenic alleles are tightly linked to a supernumerary oncogene sequence, Xmrk. The data show that the association of Xmrk with two of the tumorigenic alleles of X. variatus, P2 and Li, holds over a broad geographic area. From the distribution of the fish and the geology of the area, it is probable that this association is older than the late Tertiary. The persistence of this association suggests that Xmrk confers some benefit on P2-and Li-bearing individuals to offset the deleterious effect. The nature of this benefit remains unknown.
authors.affiliation: Department of Biology, New York University, NY 10003, USA.
authors.forename: S
authors.initials: S
authors.lastname: Kazianis
authors.forename: R
authors.initials: R
authors.lastname: Borowsky
mesh_terms: D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D003532:Cyprinodontiformes / Q000235:genetics*; D005260:Female; D029941:Fish Proteins; D008297:Male; D008546:Melanoma, Experimental / Q000235:genetics*; D008969:Molecular Sequence Data; D009857:Oncogenes; D010858:Pigmentation / Q000235:genetics*; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics*; D017978:Receptors, Growth Factor / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid
chemical_list: D029941:Fish Proteins; D017978:Receptors, Growth Factor; D020794:Receptor Protein-Tyrosine Kinases; C077101:Xmrk protein, Xiphophorus