A MUTATED GENE CAUSES DIFFICULTY OF BREEDING IN CERTAIN DOG BREEDS
It has long been believed that only dogs with flat faces, such as pugs and Pekingese breeds, have difficulty of breathing. This has been recently proven to be false because Norwich terriers also tend to wheeze. The difficulty of breathing is not caused by the shape or length of these dogs’ muzzle, but by a capricious gene.
The DNA isolated from 401 Norwich terriers showed that the terriers that suffered from respiratory tract disorders possessed a variant of the ADAMTS3 gene, usually associated with swelling surrounding the airways. According to the researchers of PLOS Genetics, almost a third of the Norwich terriers has double copies of the said gene and they had undesirable scores on their airway function tests. Their scores were worse than the dogs who had normal forms of the gene or those who had only a copy of it. The same variant of gene is also found in English and French bulldogs.