Leg Length
Short Legs (Chondrodystrophy, CDDY)
Alternative Names: Chondrodystrophy (CDDY)

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.
Breeds
Short Legs (Chondrodystrophy, CDDY) is common in:

Tibetan Spaniel

Tibetan Terrier

Coton de Tulear

Bichon Frise

Drever

Dandie Dinmont Terrier

English Toy Spaniel (King Charles Spaniel)

Perro de Presa Canario

Danish Swedish Farmdog

Papillon

Chihuahua

Chesapeake Bay Retriever

Pekingese

Basset Hound

Maltese

Dachshund (Longhaired)

Pyrenean Shepherd Dog

Polish Lowland Sheepdog

Schapendoes

Chinese Crested

American Staffordshire Terrier

Havanese

Miniature Poodle

Cardigan Welsh Corgi

Swiss Hound

Sealyham Terrier

Small Swiss Hound

Pembroke Welsh Corgi

Catahoula Leopard Dog

Bull Terrier

Finnish Lapphund

American Eskimo Dog

Miniature American Shepherd

Chow Chow

Parson Russell Terrier

Miniature Schnauzer

Shih Tzu

Field Spaniel

Dachshund (Miniature Longhaired)

Stabyhoun

Australian Shepherd

English Cocker Spaniel

Barbet

Skye Terrier

Welsh Springer Spaniel

Bavarian Mountain Hound

Miniature Pinscher

Yorkshire Terrier

Neapolitan Mastiff

Nova Scotia Duck Tolling Retriever

Japanese Chin

Lhasa Apso

Biewer Terrier

Alpine Dachsbracke

Spanish Water Dog

Scottish Terrier

Bedlington Terrier

Dachshund (Shorthaired)

American Water Spaniel

Portuguese Water Dog

American Cocker Spaniel

Puli

Kooikerhondje

Boykin Spaniel

Toy Poodle

Sussex Spaniel

Continental Toy Spaniel

Chinook

English Springer Spaniel

Cavalier King Charles Spaniel

Beagle

Löwchen

Dachshund (Miniature Shorthaired)

Clumber Spaniel

French Bulldog

Dachshund (Wirehaired)

Standard Schnauzer

Dachshund (Miniature Wirehaired)

Russian Tsvetnaya Bolonka

Mi-ki

Entlebucher Mountain Dog
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