Identification of the carrier of the Bedlington Terrier copper disease.

Copper (Cu) was assayed in serial liver biopsy specimens of 5 pups resulting from a mating of 2 Bedlington Terrier carriers of inherited Cu toxicosis; the latter were sibling offspring of an affected Bedlington Terrier and a normal dog. Between 5 and 7 months of age, 1 of the pups had acceptable hepatic Cu values in each of 6 specimens. The hepatic concentration of Cu in another pup increased steadily from 801 to 3,874 micrograms/g dry weight. The other 3 pups may be heterozygotes (carriers); in 1--the hepatic Cu peaked at 1,043 micrograms/g at 9 months, in the 2nd--at 636 micrograms/g at 7 months, and in the 3rd--at 492 micrograms/g at 7 months. Acceptable concentrations were present in these 3 dogs at 9 to 14 months. Results in the present study indicate that heterozygotes may have 1 normal and 1 abnormal controller gene for regulating their hepatic Cu metabolism, thus accounting for the increased hepatic Cu concentration only in the early months of life. The affected Bedlington Terrier with 2 abnormal genes was unable to suppress the progressive hepatic accumulation of Cu. Paired liver biopsy specimens obtained at 5 to 7 months and at 14 or 15 months of are might distinguish the heterozygote from the normal and the affected Bedlington Terrier pups.