MyDogDNA Breed Data: Irish Soft Coated Wheaten Terrier

The Irish Soft Coated Wheaten is a wheat coloured, middle-sized, terrier breed. In this article, we focus on Irish Soft Coated Wheaten Terrier breed data collected with the MyDogDNA test panel, as well as on how to use this data in practice.

Genetic Diversity in the lowest quarter compared to all dog breeds

In comparison to all dog breeds, genetic diversity of Soft Coated Wheaten Terriers is located in the bottom quarter, with the median diversity of 29.0% (picture 1). This is most probably due to the breed’s developmental history. Genetic diversity of other terrier breeds of Irish origin is also notably below average. The Irish Terrier has a particularly alarming median genetic diversity level of only 23.0%. For reference, the median diversity for mixed breed dogs is 43.3%.

Picture 1. Genetic Diversity of Soft Coated Wheaten Terriers according to the MyDogDNA database

Maintaining and even improving genetic diversity is important for every breed. It is particularly important for breeds in which the genetic diversity level is known to be low. Low genetic diversity predisposes the dog to genetic disorders by increasing the risk for inheriting the same recessive disease mutation from both parents. Low genetic diversity also increases the risk for autoimmune disorders, and predisposes to inbreeding depression.

The MyDogDNA Breeder Tool has been developed for finding the genetically most different breeding partners. This helps the breeders to maintain genetic diversity within their breed. The Breeder Tool takes also into account the hereditary diseases tested by the panel. While the Breeder Tool is widely utilized in a variety of different breeds, it is still underutilized in the Irish Soft Coated Wheaten Terrier breed. We warmly recommend Irish Soft Coated Wheaten Terrier owners to try it out!

Populations differ between countries

Picture 2 shows the genetic relationships of Irish Soft Coated Wheaten Terriers. One dot represents one tested dog. The closer the dots are to one another, the closer these dogs genetically are to each other. You can find this graph as a three-dimensional model on the Breeds page.

This picture shows that the dogs from the United States are genetically more similar to each other, but different from the populations in Britain and Finland. This graph can be utilized, for instance, when planning imports to find dogs that would bring as genetically different material as possible into the country’s population. It would be interesting to find out more about the genetic differences in Soft Coated Wheaten Terriers of other European origin.

Picture 2. Genetic relationships of Soft Coated Wheaten Terriers tested with the MyDogDNA test panel

The risk allele for Protein Losing Nephropathy included

Protein Losing Nephropathy (PLN) is a hereditary kidney disorder that causes leakage of protein into the urine. PLN has a complex background and several different genes and environmental factors can contribute to the onset of symptoms. The clinical signs include weight loss and fatigue. The condition is progressive, resulting in symptoms of kidney disease such as increased drinking (polydipsia), increased urination (polyuria), decreased appetite, nausea, and vomiting.

The MyDogDNA panel tests for an allele indicating a higher risk for PLN. Dogs homozygous for this risk allele have an increased risk for developing the condition. The risk allele was introduced to our test panel in 2015. The risk allele prevalence in the breed is as high as 62%. Genetic testing enables avoidance of carrier to carrier matings, and thus reduces the risk for puppies to be affected by the disorder. Genetic testing also enables using carriers of the disorder for breeding with genetically normal dogs, and thus maintaining genetic diversity.

Trait variants

Irish Soft Coated Wheaten Terriers are genetically mostly sable with a dark mask. Some Soft Coated Wheaten Terriers carry the e-allele causing recessive red. A small amount of Irish Soft Coated Wheaten Terriers also carry the allele causing recessive black or tan points. All tested Irish Soft Coated Wheaten Terriers are homozygous for the furnishings allele causing the dogs to have typical eyebrows and a moustache. Most Irish Soft Coated Wheaten Terriers have genetically curly coat, but some are genetically non-curly. Differences can also be seen in certain genetic variants affecting the body size.