An article co-written by SDCA Health and Genetics Chair John Dillberger, DVM PhD, has just been published in Canine Genetics and Epidemiology. Entitled “Osteosarcoma Inheritance in Two Families of Scottish Deerhounds,” you can read the entire article here, or here is the plain English summary:
Osteosarcoma (bone cancer) is the most common cancer in Scottish Deerhounds. For Deerhounds, a 2007 study concluded that a single dominant genetic factor largely governed disease risk. For Greyhounds, Rottweilers, and Irish Wolfhounds, a 2013 study found multiple genetic markers in each breed, with each marker only weakly associated with the disease.
We obtained from two breeders the pedigrees, age (if alive) or age at death, and bone cancer status for two families of Scottish Deerhounds, designated Cohorts K and T. A dog was considered unaffected only if it was free of bone cancer and at least 8.5 years old. We analyzed the data in two ways, by assuming either a single recessive genetic factor or a single dominant genetic factor.
Cohort K contained 54 evaluable dogs representing 12 litters. Cohort T contained 56 evaluable dogs representing eight litters. Bone cancer seemed clearly heritable in both cohorts; however, having a parent with bone cancer raised a pup’s risk of developing bone cancer itself to 38% for Cohort K but 78% for Cohort T, suggesting the possibility of different genetic risk factors in each cohort. In Cohort K, bone cancer inheritance fit well with a single recessive risk factor, although we could not rule out the possibility of a single dominant risk factor. In Cohort T, inheritance could be explained well by a single dominant risk factor but was inconsistent with recessive expression.
Inheritance of bone cancer in two Scottish Deerhound families could be explained well by a single genetic risk factor, consistent with a 2007 report. In one family, inheritance was consistent with dominant expression, as previously reported. In the other family, inheritance fit better with recessive expression, although the possibility of a dominant genetic factor influenced by one or more other genetic factors could not be ruled out. In either case, the results suggest that there may be at least two different genetic risk factors for bone cancer in Deerhounds.