As proposed by one of the recent studies, a pain-related inflammatory chemokine, MCP-1, showed significant increase in aqueous humor in the second eye subsequent to the first eye cataract surgery, suggesting that there might have been a sympathetic ophthalmic type uveitis in the second eye prior to the first eye surgery to explain why the second eye surgery was more painful [19]. The gene discussed is CCL2; the disease is uveitis.