MYOC and glaucoma: Myocilin has no known function (Resch and Fautsch, 2009), and there is no glaucoma phenotype in Myoc knockout mice (Gould et al., 2006; Kim et al., 2001) or in individuals with a homozygous N-terminal truncation mutation (Lam et al., 2000) or hemizygous deletion of MYOC (Wiggs and Vollrath, 2001), but rare non-synonymous coding mutations lead to toxic intracellular sequestration of misfolded myocilin (Jacobson et al., 2001; Joe et al., 2003; Yam et al., 2007).