title: Independent origin and restricted distribution of RPGR deletions causing XLPRA.
abstract: Canine X-linked progressive retinal atrophy (XLPRA) is an inherited blinding disorder caused by mutations in the ORF15 of the RPGR gene and homolog to human retinitis pigmentosa 3 (RP3). The disease is observed in 2 variations, XLPRA1 in Siberian husky and samoyed and XLPRA2 derived from mongrel dogs. A third, neutral, deletion has been described in red wolves. Haplotype analysis of the 633-kbp RP3 interval in 6 different canidae confirmed the same decent for the XLPRA1 mutation in both affected breeds but suggests a recent and independent origin for both forms of XLPRA. The RP3 interval was excluded from causative associations with blindness in the red wolf and akita, a breed closely related to Nordic sled dogs. Overall, these data suggest a limited distribution of the affected haplotypes and indicate that mutations in the ORF15 are likely to be limited to the described dog breeds.
authors.affiliation: Section of Ophthalmology, Department of Clinical Studies-Philadelphia, University of Pennsylvania, Philadelphia, USA. bzangerl@vet.upenn.edu
authors.forename: Barbara
authors.initials: B
authors.lastname: Zangerl
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Johnson
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Acland
authors.forename: Gustavo D
authors.initials: GD
authors.lastname: Aguirre
mesh_terms: D000818:Animals; D002874:Chromosome Mapping; D022202:Chromosomes, Artificial, Bacterial; D003001:Cloning, Molecular; D004283:Dog Diseases / Q000235:genetics*; D004285:Dogs; D016366:Open Reading Frames; D020641:Polymorphism, Single Nucleotide; D025064:Sex Chromosome Disorders / Q000235:genetics / Q000662:veterinary*; D014960:X Chromosome