Figure 7. Gene expression in corneas as detected by reverse transcription and real-time quantitative polymerase chain reaction. The relative expression levels of each gene in the experimental groups over naïve mice were obtained by the ΔΔCt method, as detailed in the Methods section. Since the ΔCt for naïve mice was obtained by comparing Ct with that of reference gene ribosomal protein L5 (RPL5), the expression level for this group also has a standard deviation over 1.0. * p<0.05 (n=3) as compared between the two groups. Note (#): Since matrix metalloproteinase (MMP)-13 was not detectable in the naïve mice, with the result that the ΔΔCt method did not work, the relative levels of this gene compared with RPL5 in the experimental groups was obtained by the ΔCt method.