Musladin-Leuke Syndrome

Musladin-Leuke Syndrome (MLS), previously known as Chinese Beagle Syndrome, is a genetic disease in Beagles that affects the development and structure of connective tissue.  It involves multiple body systems, including bone, heart, skin and muscle.  The disease resembles human stiff skin syndrome.  Beagles with MLS are born with several defects characterized by short outer toes on the front and sometimes all four feet, high set creased ears on a flat skull with extra cartilage in them, slant narrowed eyes and very thick tight skin with little scruff. Such pups are small in stature with a very stiff gait.  Seizures have also been noted in affected dogs.

Breeders worked with Dr. Mark Neff and provided the necessary DNA samples for his team to identify the genetic mutation responsible for Musladin-Leuke Syndrome as well as document the phenotypic presentation of the disease.  The researchers also developed a genetic test for the mutation.

The mode of inheritance for Musladin-Leuke Syndrome is homozygous recessive.  When breeders or owners submit a sample for testing, they will receive results identifying their dog in one of these three categories:

CLEAR: the dog has two copies of the normal gene and will neither develop MLS, nor pass a copy of the MLS gene mutation to any of its offspring.

CARRIER: the dog has one copy of the normal gene and one copy of the mutant gene that causes MLS. It will not develop MLS but will pass on the mutant gene to 50% (on average) of its offspring.

AFFECTED: the dog has two copies of the mutation and is affected with MLS.

Breeders can reduce the incidence of MLS by testing their breeding stock and making breeding decisions that avoid producing offspring with two copies of the mutation.  The test can also be used by Beagle owners to confirm diagnosis if there is a question about whether a dog is affected.

To order the test kit, visit the University of California, Davis Veterinary Genetics Laboratory at http://www.vgl.ucdavis.edu/services/MLS.php.