Absence of Glaucoma in Tg-MYOCY437H Mice of Diverse Genetic Backgrounds.

PURPOSE: Mutations in the myocilin (MYOC) gene cause elevated intraocular pressure and glaucoma. To better understand the factors influencing susceptibility to glaucoma, we studied the MYOC mutation (MYOCY437H). METHODS: We characterized ocular phenotypes in Tg-MYOCY437H mice on nine different mouse strain backgrounds. RESULTS: No glaucoma-related phenotypes were observed. We detected neither elevated intraocular pressure (daytime readings) nor optic nerve degeneration differences between wild type (WT) and Tg-MYOCY437H mice. This included an absence of Tg-MYOCY437H-induced phenotypes on a mixed B6SJL background that best reflected the original publications with this strain. We confirmed that this result was not due to an absence of transgene expression in ocular tissues. CONCLUSIONS: Our data indicate undefined complexity and that the previously reported glaucoma phenotypes are not robust across all institutions and environments.