Many dog breeds are defined by the presence of shortened legs that result from abnormal growth of cartilage and changes in the structure of growth plates. This leads to shortened leg bones that exhibit a bowed appearance. Two conditions have been described that cause shortened legs and are known as Chondrodysplasia (CDPA) and Chondrodystrophy (CDDY). CDDY is the second mutation that leads to shorter legs and more importantly can also put a dog at risk for premature degeneration of intervertebral discs known as Intervertebral Disc Disease (IVDD). The intervertebral disc sits between the vertebrae and allows for flexibility of the vertebral column. In dogs that carry the CDDY mutation, premature calcification can lead to degeneration of discs in dogs at a young age resulting in herniation, inflammation, and hemorrhage in the spinal cord. This can ultimately lead to severe pain and neurological dysfunction typical for IVDD.

• Basset Hound
• Beagle
• Bichon Frise
• Cardigan Welsh Corgi
• Cavalier King Charles Spaniel
• Chesapeake Bay Retriever
• Chihuahua
• Chinese Crested
• American Cocker Spaniel
• Coton de Tulear
• Dachshund
• Dandie Dinmont Terrier
• English Springer Spaniel
• French Bulldog
• Havanese
• Jack Russell Terrier
• Miniature Dachshund
• Nova Scotia Duck Tolling Retriever
• Pekingese
• Pembroke Welsh Corgi
• Poodle (Miniature and Toy)
• Portuguese Water Dog
• Sealyham Terrier
• Scottish Terrier
• Shih Tzu
• Teddy Roosevelt Terrier

A (CLEAR/NORMAL): These dogs have two copies of the normal gene and do not possess the mutation that leads to shortened legs and increased IVDD risk

B (CARRIER/AFFECTED): These dogs have one copy of the normal gene and one copy of the mutation associated with shortened legs and increased IVDD risk. They will have shortened legs and are at risk for IVDD. If bred, these dogs will pass the mutation to 50% of their offspring, on average.

C (AT RISK/AFFECTED): These dogs have two copies of the mutation associated with shortened legs and increased IVDD risk. They will have shortened legs and are at risk for IVDD. If bred, these dogs will pass the mutation to 100% of their offspring, on average.

Many dog breeds are defined by the presence of shortened legs that result from abnormal growth of cartilage and changes in the structure of growth plates. This leads to shortened leg bones that exhibit a bowed appearance. Two conditions have been described that cause shortened legs and are known as Chondrodysplasia (CDPA) and Chondrodystrophy (CDDY). CDPA is caused by a mutation in a bone development gene on chromosome 18 called FGF4. This mutation is very common in breeds such as Basset Hound, Welsh Corgi, Dachshund, West Highland White Terrier and Scottish Terrier and is inherited in a dominant fashion. This means a dog only needs to inherit one copy of the mutation to exhibit shortened legs. This mutation has also been reported to explain shortened legs in other breeds currently including Jack Russel Terriers, Dandie Dinmont Terriers, French Bulldogs, Chihuahua, Chinese Crested, Pekingese, Shih Tzu, Havanese, Coton de Tulear, Bichon Frise, Miniature and Toy Poodle, Beagle, Cavalier King Charles Spaniel, English Springer Spaniel, American Cocker Spaniel, Portuguese Water Dog, Nova Scotia Duck Tolling Retriever or Chesapeake Bay Retriever.

• Basset Hound
• Beagle
• Bichon Frise
• Cardigan Welsh Corgi
• Cavalier King Charles Spaniel
• Chesapeake Bay Retriever
• Chihuahua
• Chinese Crested
• American Cocker Spaniel
• Coton de Tulear
• Dachshund
• Dandie Dinmont Terrier
• English Springer Spaniel
• French Bulldog
• Havanese
• Jack Russell Terrier
• Miniature Dachshund
• Nova Scotia Duck Tolling Retriever
• Pekingese
• Pembroke Welsh Corgi
• Poodle (Miniature and Toy)
• Portuguese Water Dog
• Scottish Terrier
• Shih Tzu
  
• Teddy Roosevelt Terrier

A (CLEAR/NORMAL): These dogs have two copies of the normal gene and do not possess the mutation that leads to shortened legs.

B (CARRIER/AFFECTED): These dogs have one copy of the normal gene and one copy of the mutation associated with shortened legs. They will have shortened legs and, if bred, will pass the mutation to 50% of its offspring, on average.

C (AT RISK/AFFECTED): These dogs have two copies of the mutation associated with shortened legs. They will have shortened legs and, if bred, will pass the mutation to 100% of its offspring.