After abnormal expression of the p53 gene being found in epithelium, pterygium is now considered to be a result of uncontrolled cell proliferation, like a tumour.^1,2

The p53 gene is a tumour suppressor gene, whose function is mediated by stimulation of p21 (Waf-1) gene, another tumour suppressor gene, to control cell cycle and prevent tumour formation.³ Mutations in either p53 or p21 are detected in many tumour cells,^3,4 and polymorphisms of p53 codon 72 or p21 codon 31 were found to be associated with many tumours.^5,6

Because of the abnormal expression of the p53 gene in pterygium epithelium^1,2 and there is evidence that hereditary factors may have a role in the development of pterygium,^7,8 it is logical to suspect the correlation between pterygium formation and p53 and …