Data for: Global frequency analyses of canine progressive rod-cone degeneration–progressive retinal atrophy and collie eye anomaly using commercial genetic testing data

Hundreds of genetic variants associated with canine traits and disorders
have been identified, with commercial tests offered. However, the
geographic distributions and changes in allele and genotype frequencies
over prolonged, continuous periods of time are lacking. This study
utilized a large set of genotypes from dogs tested for the progressive
rod-cone degeneration–progressive retinal atrophy (prcd-PRA) G>A
missense PRCD variant (n = 86,667) and the collie eye anomaly
(CEA)-associated NHEJ1 deletion (n = 33,834) provided by the commercial
genetic testing company (Optigen/Wisdom Panel, Mars Petcare Science
& Diagnostics). These data were analyzed using the chi-square
goodness-of-fit test, time-trend graphical analysis, and regression
modeling in order to evaluate how test results changed over time. The
results span fifteen years, representing 82 countries and 67 breeds/breed
mixes. Both diseases exhibited significant differences in genotype
frequencies (p = 2.7 × 10−152 for prcd-PRA and 0.023 for CEA) with
opposing graphical trends. Regression modeling showed time progression to
significantly affect the odds of a dog being homozygous or heterozygous
for either disease, as do variables including breed and breed popularity.
This study shows that genetic testing informed breeding decisions to
produce fewer affected dogs. However, the presence of dogs homozygous for
the disease variant, especially for prcd-PRA, was still observed fourteen
years after test availability, potentially due to crosses of unknown
carriers. This suggests that genetic testing of dog populations should
continue.