Figure 3. Tyrp1 and Gpnmb genotypes do not influence IOP but do influence the TID phenotype. A: BXD strains carrying wild-type alleles of Tyrp1 and Gpnmb (WT/WT) had intraocular pressure (IOP) values that ranged between 10 and 21 mmHg (green bars). Mice with mutant alleles of both genes (red bars) had a similar range of IOPs. B: When plotted in the same rank order as IOP, the transillumination defect (TID) values had no pattern in ranking. At 6 to 9 months, the only BXD strains that had TID grades above 0 were those that had mutations in Tyrp1. Those lacking mutations in either gene had little to no TID, despite having elevated IOPs in some cases. The n values range from 4 to 13 mice per BXD strain.