Figure 3. Differential messenger ribonucleic acid expression of the target genes via semiquantitative reverse transcription–polymerase chain reaction (RT-PCR; 24^th cycle). This figure shows the results of the RT–PCR products in 2% agarose gel electrophoresis, stained with ethidium bromide. Lanes 1 to 10: Keratoconus (KCN) corneas; lane 11: pooled normal corneas and lane 12: negative control without RT. The fluorescent intensity of the bands was quantified with a GS-800 densitometer. The signal intensities were normalized to values obtained for beta 2 microglobulin (B2M). The messenger ribonucleic acid (mRNA) expression of transforming growth factor, beta 1 (TGF-β1), and dual-specificity phosphatase 1 (DUSP1) was increased in the KCN corneas (three- and fivefold, respectively; both p<0.05). The comparative superoxide dismutase 1 (SOD1) mRNA level showed no difference between the KCN and non-KCN samples.