Important molecules in pterygium pathogenesis. A and C. Ethidium bromide stained gel images from semi-quantitative reverse transcription polymerase chain reaction. A. Using specific primers against PSP57 (amplicon length of 452 bp) and PSP94 (amplicon length of 350), PCR products corresponding to PSP94 could be visualised at 30 cycles, whereas PSP57 products could only be just detected at 40 cycles. The sequences were confirmed by sequencing the specific band after cutting the band and extraction of DNA. Note that in patients 1–3, PSP94 transcripts were up-regulated in pterygium relative to conjunctival controls. B. Western blot images, using specific antibodies against MSMB and GADPH (loading control). Note that the PSP proteins were up-regulated in pterygium relative to controls. C. The alternative spliced forms of fibronectin transcripts ED-A and ED-B were detected by visualisation of PCR products. Note that all forms of the transcripts were up-regulated in pterygium compared to conjunctival controls.