Dominant and Recessive Characteristics in Dogs

Apr 26, 2011
Karen Jackman

The living, breathing, phenotype dog is a combinat - Karen Jackman

Your beloved pooch is actually, from a dog breeder's point of view, three dogs in one.

Genetically speaking, every dog is actually three dogs: shadow, substance and the combination of the two. The shadow dog is the unseen recessive genes which may be expressed in future generations. The substance dog is the living dog (the phenotype). The gene-complex dog is the collection of its complete gene collection, dominant and recessive (the genotype). Most of the traits dog owners and breeders want in their phenotype dogs are controlled by complex genes called polygenes. There is a list of dominant and recessive traits agreed upon by most geneticists and breeders.

Factors Affecting Characteristics

Most dog traits are controlled by numerous polygentic gene pairs and factors such as incomplete dominance and penetrance. Polygenetic traits are composed of dominant and recessive genes. Incomplete dominance is a form of intermediate inheritance in which one allele -- one member of a gene pair -- for a specific trait is not completely dominant over the other allele. This results in a dog which has a combination of recessive and dominant characteristics. Pentrance is the proportion of individual dogs which carry a particular variation of a gene that also expresses an associated trait. It's important for breeders to familiarize themselves with the list of accepted dominant and recessive characteristics in general.

Dominant Traits in Dogs

A dog with dominant characteristics present in the head area may have low-set ears, long ears, a long head, wide ear leather, dark eyes, correct bite, black nose and a short face; and in the body area, it presents as a deep chest, straight top line, straight tail, high tail set, heavy bone, compact feet, a short coat and a choppy gait. A dominant dog will generally be intelligent and he may have a more aggressive temperament.

Canine Recessive traits

A dog with recessive characteristics present in the head area as having a large skull, short ears, a fine skull, light eyes, bulging eyes and overshot/undershot bite; and in the body area as a having long, reaching gait, a low tail set, no feathering on tail, a kinked tail, a long coat, longer and straight legs.

These dogs usually have mild, non-aggressive temperaments and a lack of intelligence.

Pedigrees

How pedigrees are made can be better understood using the three-dogs-in-one concept. Patterns of genetic activity are observed and decisions made to allow for the best chance of creating the desired phenotype dog. Breeders know dominant traits do not skip generations while recessive traits may skip multiple generations. For the best chance of getting a living, breathing puppy with a recessive trait it must be inherited from both parent dogs. Knowledge about genetic activity allows breeders to encourage desirable traits while avoid those they consider undesirable.