Molecular genetic alterations and viral presence in ophthalmic pterygium (review)

Pterygium is a lesion of the corneoscleral limbus which tends to grow in si ze, often recurs after surgical excision and is associated with exposure to solar light. Additionally, a family history is frequently reported. Loss o f heterozygosity (LOH), increased P53 expression and the presence of oncoge nic viruses, such as human papilloma virus (HPV) and herpes simplex virus ( HSV), have been detected in pterygia, supporting the possible neoplastic na ture of the lesion. Coinfection by HSV and HPV as well as LOH at some loci have also been correlated with clinical features, such as postoperative rec urrence and history of conjunctivitis. A possible model of pterygium format ion is proposed, in which genetic predisposition, environmental factors and viral infection(s) participate in a multi-step process. Future research ma y lead to new ways of pterygium treatment such as anti-viral or gene therap y.