Research
Identification of DNA Test
Over the course of a number of years, several breeders saw what appeared to be isolated cases of puppies forming this extremely rare type of stone. The experiences of these breeders came together at the 2014 American National during discussion of a recently affected litter. Janna Morgan pursued investigation of the disease further and ended up working with Dr. Furrow. Dr. Furrow and her colleagues identified a MOCOS mutation (type II xanthinuria) in all of the affected puppies and developed a DNA test to screen for this mutation. Dr. Furrow worked with breeders of the affected puppies to identify dogs related to known cases (sires, dams, littermates and other close family members) as well as a selection of unrelated dogs.
A total of 43 Toy Manchesters were tested. Three of them were affected and symptomatic, one carries two copies of the genes but has not had any health issues, and 9 are carriers. The other 30 dogs are clear of the mutation. The population tested to date is obviously skewed because Dr. Furrow intentionally included dogs that were closely related to the affected pups and thus more likely to be carriers. However, it still suggests that this mutation is not as rare in the breed as we had hoped. Hereditary xanthinuria does occur in other dog breeds, but the mutations are different. We have identified distinct XDH and MOCOS mutations in other breeds with xanthine stones.
Standard Manchester Terriers
In September 2016, the Canadian Manchester Terrier Club sponsored testing of a random group of Standard Manchester Terriers. Most participants were selected at the 2016 American Manchester Terrier Club National Specialty with a goal of sampling dogs from diverse lines. Dogs selected were from classically "Standard Manchester" lines and did not include any individuals with Toy ancestors in their recent background.
A total of 25 Standard Manchesters have been tested for both Juvenile Cardiomyopathy and Xanthinuria. All 25 tested clear for both mutations.
The CMTC wishes to thank all participants for so generously assisting with this initiative.
Over the course of a number of years, several breeders saw what appeared to be isolated cases of puppies forming this extremely rare type of stone. The experiences of these breeders came together at the 2014 American National during discussion of a recently affected litter. Janna Morgan pursued investigation of the disease further and ended up working with Dr. Furrow. Dr. Furrow and her colleagues identified a MOCOS mutation (type II xanthinuria) in all of the affected puppies and developed a DNA test to screen for this mutation. Dr. Furrow worked with breeders of the affected puppies to identify dogs related to known cases (sires, dams, littermates and other close family members) as well as a selection of unrelated dogs.
A total of 43 Toy Manchesters were tested. Three of them were affected and symptomatic, one carries two copies of the genes but has not had any health issues, and 9 are carriers. The other 30 dogs are clear of the mutation. The population tested to date is obviously skewed because Dr. Furrow intentionally included dogs that were closely related to the affected pups and thus more likely to be carriers. However, it still suggests that this mutation is not as rare in the breed as we had hoped. Hereditary xanthinuria does occur in other dog breeds, but the mutations are different. We have identified distinct XDH and MOCOS mutations in other breeds with xanthine stones.
Standard Manchester Terriers
In September 2016, the Canadian Manchester Terrier Club sponsored testing of a random group of Standard Manchester Terriers. Most participants were selected at the 2016 American Manchester Terrier Club National Specialty with a goal of sampling dogs from diverse lines. Dogs selected were from classically "Standard Manchester" lines and did not include any individuals with Toy ancestors in their recent background.
A total of 25 Standard Manchesters have been tested for both Juvenile Cardiomyopathy and Xanthinuria. All 25 tested clear for both mutations.
The CMTC wishes to thank all participants for so generously assisting with this initiative.