Brachycephaly

General Information: Brachycephaly (BR) is a congenital trait in dogs resulting from selective breeding, leading to a noticeably shortened skull and snout. Prominently observed in breeds such as pugs, bulldogs, and boxers, it can be characterized by a distinctive short, upward-pointing muzzles, rounded heads, and occasional underbites. Affected dogs may experience a range of health issues related to their unique cranial structure, including breathing difficulties, dental problems, and an increased risk of heat intolerance. The trait is influenced by multiple genes, with a significant variant found in the BMP3 gene contributing to the reduced muzzle length. The skull shape is determined by various genetic factors, which means that not all dogs with brachycephalic features will carry the same genetic variants.

How to Read Your Dog's Test Results for this Genetic Variant:

Two Variants Detected: Dog Likely Affected

One Variant Detected: Dog Unlikely Affected

No Variants Detected: No Effect

Gene / Testing Information: Genetic testing for Brachycephaly (BR) primarily involves evaluating the BMP3 gene for the presence of the “br” variant, which is linked to a short muzzle in certain dog breeds. Brachycephaly is inherited in a multifactorial manner, meaning that multiple genes, including BMP3, contribute to the trait. Dogs inheriting two copies of this BMP3 variant (br/br) are more likely to exhibit pronounced brachycephalic features, while those with one or no copies (BR/BR or BR/br) typically have longer muzzles. However, other genetic variations, such as mutations in the SMOC2 gene, also play a role in determining head shape. Genetic testing is crucial for breeding practices, as it helps identify dogs carrying the brachycephalic-associated mutations, allowing breeders to make informed decisions to avoid potential health issues related to extreme skull shortening. By carefully selecting breeding pairs, breeders can work towards maintaining or modifying this trait in their lines while ensuring the overall health and well-being of the dogs.