Читать книгу Pet-Specific Care for the Veterinary Team - Группа авторов - Страница 263

A cocker spaniel breeder takes your advice and performs DNA testing for phosphofructokinase deficiency on a prospective breeding pair. The potential sire is clear, but the bitch is determined to be a carrier. What are the odds that this mating will result in affected pups?

Because the sire is clear, he must be homozygous for the normal allele (PP). The bitch, as a carrier, has the heterozygous genotype Pp. A mating of these two would produce roughly 50% homozygotes (PP) and 50% carriers (Pp), but no affected individuals (pp). Given the new technology, which allows genotypic determination for this trait in cocker spaniels, the occurrence of affected individuals can be completely eliminated even when it may be difficult to completely eliminate the recessive allele itself from a population.