VetGen - The leader in veterinary genetic disease research and genetic disease detection services for purebred animals

Optimal Canine Pedigree Types

First, let us provide definitions of some key genetic terms used in describing various types of pedigrees (the terms below are used for recessively inherited diseases):

This indicates a dog which does not have the disease gene present.
This indicates a dog which has one disease gene and one normal gene but the dog itself may not exhibit any signs of disease.
This indicates a dog which will -- or currently does -- show signs of the disease because it has two disease genes.

This symbol indicates a female.
This symbol indicates a male.
or These symbols indicate either clear or carrier dogs.
or These symbols indicate affected dogs.

Recessive Inheritance
This means that a dog must have two disease genes in order to be affected with the disease.
Dominant Inheritance
This means that the dog will be affected with only one copy of the disease gene.


  • In all cases, collected samples are most informative if there are at least two offspring (either brothers and sisters or half-brothers and sisters) affected with the disease.
  • While the sex of affected animals is indicated in the pedigrees listed below, sex of the animals is irrelevant to our research.
  • Pedigrees with more than one known affected dog are useful even if a sample is available from only one affected dog.
  • Samples from unaffected offspring are less useful than samples from affected offspring but should be collected when available. These samples are important especially when the parents are not available for sample collection.

VetGen is looking for pedigrees where there is a presence of a Genetic Disease which is part of our current research program.

The following are examples of pedigrees that would be useful for our research in trying to locate disease genes.

Pedigree Example Number 1

In this example

  • both parents would be carriers
  • their offspring would include at least 2 affected

We would be interested in samples from
  • the affected offspring
  • their parents
  • the siblings of the affected offspring

Pedigree Example Number 2

In this pedigree

  • two (or more) bitches were bred to the same stud dog or a bitch was bred to more than one stud dog
  • affected dogs showed up in these different litters

We would be interested in samples from
  • affected dogs are half-brothers or sisters
  • any affected offspring
  • all three of the parents
  • other siblings from any of the litters

Pedigree Example Number 3

In this pedigree

  • one of the parents is affected with the disease
  • offspring would include at least two affected dogs

We would be interested in samples from
  • the affected offspring
  • both of the parents
  • other available offspring

Pedigree Example Number 4

In this example

  • two or more affected siblings are available
  • their parents are not

We would be interested in samples from
  • the affected dogs
  • unaffected siblings where available

Pedigree Example Number 5

In this example

  • an affected has been used in several different breedings
  • one or more affected offspring are available from different breedings

We would be interested in samples from
  • the affected offspring
  • siblings of the affected

Dog lovers who have useful pedigrees and are interested in helping VetGen's research should contact us.