GNE and GNE myopathy: GNE myopathy (GNEM; OMIM 605820) is an autosomal-recessive disease, caused by mutations in the gene encoding the bi-functional UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE), which is the key enzyme of the sialic acid biosynthesis [1,2].