Skeletal dysplasias are inherited defects of bone growth leading to disproportionate dwarfism in several breeds. The long bones of the forelimbs are most severely affected, whereas the length and depth of the body is normal. Adult dogs with disproportionate dwarfism are overbuilt and stand on too short legs. We have identified the causative mutation for a relatively mild form of disproportionate dwarfism in Labrador Retrievers, which we termed 'skeletal dysplasia 2 (SD2)'. Affected dogs have slightly shorter legs but according to our knowledge no other health problems such as e.g. secondary arthrosis. SD2 is genetically distinct from retina dyplasia/oculoskeletal dysplasia (RD/OSD), which leads to severe health problems.
A genetic test, which allows the unquivocal diagnosis of carrier animals is offered by several commercial testing laboratories.