The content of WSC, especially glucose and sucrose, in grass is of relevance for horses with insulin dysregulation (Frank et al., 2010; Lindåse et al., 2016), pituitary pars intermedia dysfunction (McGowan, 2008), or polysaccharide storage myopathy (Firshman et al., 2003; Borgia et al., 2011). The gene discussed is INS; the disease is myopathy.