DLG1 and pneumocystosis: The present results, which were mostly obtained using a Dlg1 gene-null mutant mouse strain with its genome derived from the C57BL/6N and CBA/J mouse strains, also indicate a role for DLG1 in PCP phenomena, generally supporting the opinion of Rivera et al. However, the phenotypes described in Rivera et al. and our present report consist of not only universal phenotypes that were observed in all three mouse strains, but also specific phenotypes with varied severity or incidence depending on the different mouse strains.