Abstract:
Polyphasic skeletal muscle degeneration, necrosis and mineralization of skeletal muscle
was diagnosed in eight juvenile free-ranging lions (Panthera leo), from five different litters in the
Greater Kruger National Park area that were unable to walk properly. A detailed investigation was not
possible in free-ranging lions, so the cause could not be determined. The cases resembled hypokalemic
polymyopathy in domestic cats with muscle weakness. A candidate-gene approach previously
identified a nonsense mutation in the gene coding for the enzyme lysine-deficient 4 protein kinase
(WNK4) associated with the disease in Burmese and Tonkinese cats. In this study, we sequenced all
19 exons of the gene in one case, and two control samples, to identify possible mutations that may
be associated with polymyopathy in free-ranging lions. Here, no mutations were detected in any of
the exons sequenced. Our findings indicate that the WNK4 gene is not a major contributor to the
condition in these lions. Further studies into the pathogenesis of this condition are needed to inform
conservation policies for this vulnerable, iconic African species
