To access the data, click or select the words “Appendix 1.” H2 is a Siberian husky founder that was outcrossed to dogs from various breeds. The following abbreviations were used: (B) beagle, (N) mixed breed control, and (E) Norwegian elkhound-derived outcross. Severely affected dogs are in black, moderately affected dogs in dark gray, and mildly affected dogs in crosshatch pattern. Squares represent male and circles represent female. Dotted circles are carrier females that were not included in the phenotype analysis. (Figure was modified from our previously published article [22]).