Frequency of Osteosarcoma Among First-Degree Relatives of St. Bernard Dogs2

Publisher Website
Google Scholar
Abstract
Osteosarcoma (OS) was found in 6 of 148 first-degree relatives of 21 index St. Bernard dogs with histologically proved OS, but was not found in any of the 110 first-degree relatives of 18 breed-, age-, and sex-matched controls. Analysis of a composite pedigree constructed from individual four-generation pedigrees showed that all 21 index dogs were related. The average coefficient of relationship for members of the OS-bearing group was significantly higher than that for members of the control group. The average coefficient of inbreeding of the OS-bearing group was lower than, but not significantly lower than, that of the controls. This suggests that the presence of specific genes within certain family lines, and not inbreeding per se, influences susceptibility to OS. The lack of information on entire litters precluded the formal testing of specific genetic hypotheses, but examination of the pedigree excludes fully penetrant autosomal dominant and X-linked recessive inheritance. Other monogenic models or more complex modes, perhaps involving an interaction between genetic and environmental factors, cannot be excluded, nor can vertical transmission of an infectious agent. Based on the familial pattern of occurrence of affected dogs, developing a strain with a high incidence of OS should be possible by selective breeding. A method for identifying ancestors having a major contribution to the genome of the group of index dogs is described.

This publication has 5 references indexed in Scilit: