Other name: Chr X-related Progressive Retinal Atrophy (XLPRA1), RPGR
 Affected gene: RPGR
 Inheritance: Recessive, linked to the X chromosome
 Mutation:  ROS_Cfam_1.0  CanFam6 ChrX g.20425884-20425888 (del GAGGA)
 OMIA Link: 000831-9615

 * In hereditary genetic diseases linked to the X chromosome, the following rules apply:
 -For a recessive disease, the male is affected (at risk of developing the disease) even if he only has one copy of the mutation.
 -Transmission from a male to a male does not exist, because a male never transmits his X chromosome to his sons.
 -All females of an affected male will inherit the mutant gene.
 -Females who are carriers have a 50% chance of passing the mutant gene to their sons and daughters.

Breeds suitable for testing:  Samoyed, Siberian Husky
 Reference:
 Zhang, Q., Acland, GM., Wu, WX., Johnson, JL., Pearce-Kelling, S., Tulloch, B., Vervoort, R., Wright, AF., Aguirre, GD. : Different RPGR exon ORF15 mutations in Canids provide insights into photoreceptor cell degeneration. Hum Mol Genet 11:993-1003, 2002. Pubmed reference: 11978759.