5 Genetic Analysis of the Canid Skeleton: Morphological Loci in the Portuguese Water Dog Population

Abstract

Science has often been likened to a voyage of discovery. During my more than 50 years as a research scientist, that has never been more evident than in our journey into the quantitative genetics of dog morphology. The death of our first Portuguese water dog, Georgie, brought our laboratory into contact with Karen Miller, a dog breeder intensely interested in dog genetics. This happenstance, coupled with the fortuitous population structure of this breed, led into a collaboration between our laboratory and dog owners/breeders that revealed a world of unexpected treasures, all the more beautiful because of their simplicity. (K.G.L.)

In what follows, we demonstrate that dog populations with good pedigrees will allow estimation of relatedness within the population. This, coupled with accurate phenotypic data from owners, allowed us to look at heritabilities of phenotypes and the relation of heritable traits to the founders of the population. The availability of such data led to the genetic analysis of polygenic phenotypes. Grouping correlated traits using principal component (PC) analysis allowed us to look for underlying biological structure. Eventually, with the use of genetic markers, it became possible to look for quantitative trait loci (QTLs) regulating individual traits such as diseases, as well as those that regulate combinations of traits representing a higher level of genetic control. Our results are a prelude to much more that will come from the study of the dog.

DEVELOPING THE SYSTEM
Feasibility
Canine isolates with accurate pedigree information can provide an excellent compromise in the trade-off between...