Musladin-Leuke Syndrome (MLS)



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Musladin-Leuke Syndrome (MLS)


Musladin-Leuke Syndrome (MLS) is a recessive mutation that affects Beagles. The mutation prevents normal formation of the skin and connective tissue, affecting the dog's appearance and gait.


A beagle with MLS may be smaller in size and walk on his toes rather than on the pad of the foot. Other symptoms include a flattened head shape, tight and stiff fur, and slanted eyes. A wide range of severity is associated with MLS, so some dogs may experience mild to moderate symptoms. Others, however, may be severely impaired. There is no cure for MLS. This condition is not fatal, though some dogs affected by MLS may also experience seizures. Proper veterinary care can help maintain a positive quality of life for dogs affected by MLS.


The mutation causing MLS is autosomal recessive, meaning that both parents would have to contribute a copy of the mutation to produce offspring with MLS. Carriers of the mutation are asymptomatic; genetic testing can identify these carriers to prevent breeding puppies with MLS.

Acceptable Sample Types:

Animal Genetics accepts Buccal Swab, Blood, Dewclaw. Complimentary sample collection kits are available and can be ordered at test now.

This Test Is Relevant For the Following Breeds:

  • Beagle


Animal Genetics offers DNA testing for Musladin-Leuke Syndrome (MLS). The genetic test verifies the presence of the mutation and presents results as one of the following:

MLS/MLS Affected The dog carries two copies of the mutant gene and is homozygous for MLS. This dog will be affected and will always pass a copy of the mutation to its offspring.
MLS/n Carrier Both the normal and mutant copies of the gene were detected. Dog is a carrier for the MLS mutation and can pass on a copy of the defective gene to its offspring 50% of the time.
n/n Clear Dog tested negative for the MLS gene mutation and will not pass on the defective gene to its offspring.