Leg Length

Short Legs (Chondrodystrophy, CDDY)

Alternative Names: Chondrodystrophy (CDDY)

Short Legs (Chondrodystrophy, CDDY) Photo

The Short Legs (Chondrodystrophy, CDDY) variant is associated with shortened legs secondary to skeletal dysplasia which affects the development of cartilage and bone growth. The variant is an insertion of an FGF4 gene on chromosome 12. There is another common Short Legs variant that occurs on chromosome 18, called breed-defining chondrodysplasia (CDPA), which has a greater effect on leg length. While the CDDY variant has a less pronounced effect on stature, it is associated with an increased risk for abnormal early degeneration of intervertebral discs in the spine.

More Info

Did you know?

The Short Legs (CDDY) variant is widely found in Beagles, Cavalier King Charles Spaniels, Dachshunds, French Bulldogs, Pembroke and Cardigan Welsh Corgis, and many more. It was discovered in 2017 by researchers at University of California, Davis.

How it works

Dogs with one copy of the Short Legs (CDDY) variant typically have some shortening of their legs, whereas dogs with two copies can have more obvious shortening. Dogs that inherit both variants associated with short legs (CDDY and CDPA) tend to show a more drastic reduction in leg length.

Health implications

One or two copies of the Short Legs (CDDY) variant is associated with an elevated risk of developing intervertebral disc disease (IVDD). IVDD is a degenerative disc condition that can lead to spinal disc herniation, pain and potential paralysis. Some affected dogs may require surgical intervention. However, please note the Short Legs (CDDY) variant is a risk factor and some dogs with one, or even two, copies of this variant may not go on to show signs of disc disease. Additionally, risk levels appear to vary significantly by breed. Therefore, further research is needed to identify additional genetic variants which may influence IVDD risk. You can read more about the associated health risks of this variant within the Health section, under the test name Chondrodystrophy (CDDY) and Intervertebral Disc Disease (IVDD) Risk.

Prevalence

2 in 10 dogs

have one or more copy of this genetic variant in our testing.

Technical Details

Gene FGF4
Variant Insertion
Chromosome 12
Coordinate 33,710,178

All coordinates reference CanFam3.1

References & Credit

Credit to our scientific colleagues:

Brown, E.A., Dickinson, P.J., Mansour, T., Sturges, B.K., Aguilar, M., Young, A.E., … Bannasch, D.L. (2017). FGF4 retrogene on CFA12 is responsible for chondrodystrophy and intervertebral disc disease in dogs. Proc Natl Acad Sci U S A, 114(43), 11476-11481. View the article