UK pedigrees
The UK pedigrees were provided by the owners of the dogs. All cases reported here have had a veterinary diagnosis of kidney disease (JKD) and have a completed a form that gives permission to publish the pedigree.
Cases 109 – 118 came from a veterinary research study on the disease in a cohort of dogs from over 10 years ago.
Parents of all cases are shown in blue, indicating that they are either the sire or the dam of at least one affected puppy. Colour - coding of these dogs when present as ancestors in other pedigrees, merely indicates that they have been parents of a reported case. It does not imply that these dogs are necessarily responsible for the inheritance of the disease in subsequent pedigrees.
No attempt is made at this stage to interpret the pedigrees and identify sources of the JKD mutation.
Coefficients of inbreeding (COI) are located above each pedigree. The COI were obtained using UK KC website, some others were estimated from the 5-generation pedigrees available. These COI levels therefore do not include the historical inbreeding that is included in KC values and are underestimates
Cases 109 – 118 came from a veterinary research study on the disease in a cohort of dogs from over 10 years ago.
Parents of all cases are shown in blue, indicating that they are either the sire or the dam of at least one affected puppy. Colour - coding of these dogs when present as ancestors in other pedigrees, merely indicates that they have been parents of a reported case. It does not imply that these dogs are necessarily responsible for the inheritance of the disease in subsequent pedigrees.
No attempt is made at this stage to interpret the pedigrees and identify sources of the JKD mutation.
Coefficients of inbreeding (COI) are located above each pedigree. The COI were obtained using UK KC website, some others were estimated from the 5-generation pedigrees available. These COI levels therefore do not include the historical inbreeding that is included in KC values and are underestimates
Conclusions
- The observation that the disease almost invariably occurs in family groups establishes that JKD is inherited.
- The observation that inbreeding on JKD breeding is commonly involved, or that JKD producers are present in the background of both parents irrespective of country of origin, strongly suggests a recessive mode of inheritance.
- Evidence that males can breed prior to developing the disease is shown. On a recessive inheritance all the progeny of such a male will carry the disease gene.
- However, the partially-hidden nature of the disease and the probability that affected dogs may survive and breed normally pose further problems that need to be resolved.
- Levels of inbreeding in many of the JKD pedigrees are extremely high, notably in the show section of the breed, indicates that inbreeding has played a significant role in the emergence of detectable disease in the UK.