Breeds Affected: Beagle
Samples Accepted: Blood, Buccal Swabs
Disease Information: Dogs affected with MLS have short stature, extremely thick, taut skin and restricted joint mobility which leads to a hopping “tip-toe” type of gait. This is accompanied with eyes set wide in broad skulls, creased ears, and occasional seizures and bouts of unexplained pain. Failure to thrive is a problem, but if pups survive past one year of age, the condition stabilizes. Most affected adult dogs also have arthritis.
Inheritance Information: MLS is autosomal recessive, meaning that animals with two copies of this allele will be affected. Animals with one copy of the gene will be clinically-normal carriers.
The possible genotypes are:
N/N The dog is normal, and cannot produce affected offspring.
N/mls The dog is a carrier, and can pass the allele on to approximately 50% of any offspring. If bred to another N/mls carrier, approximately 25% of the offspring will be normal, 50% will be carriers, and 25% will be affected.
mls/mls The dog is affected. If bred to a normal animal, 100% of the offspring will be carriers. If bred to an N/mls carrier, 50% of the offspring will be carriers and 50% will be affected.
– Carriers may be bred to normal animals (N/mls x N/N) without any risk of producing affected offspring. The offspring should be tested before breeding to determine if they are carriers or normal.
– Breeding two carriers (N/mls x N/mls) is not recommended due to the possibility of 25% of the offspring being affected.
– Affected animals (mls/mls) should not be used for breeding.
Test Information: This mutation test identifies a single base pair change in exon 7 of the ADAMTSL2 gene.
Bader, HL., Ruhe, AL., Wang, LW., Wong, AK., Walsh, KF., Packer, RA., Mitelman, J., Robertson, KR., O’Brien, DP., Broman, KW., Shelton, GD., Apte, SS., Neff, MW.: An ADAMTSL2 founder mutation causes Musladin-Lueke Syndrome, a heritable disorder of beagle dogs, featuring stiff skin and joint contractures. PLoS One 5:, 2010. Pubmed reference: 20862248. Doi: 10.1371/journal.pone.0012817.
Further information is available at the Online Mendelian Inheritance in Animals website.