H2AX and ocular melanoma: In our study, although higher levels of γ-H2AX were observed when the patients received a higher dose of irradiation, indicating that the γ-H2AX assay reflected the accumulation of incomplete repair of sublethal damage, the enhancements of γ-H2AX expression on the fourth and last days after fractionated irradiation were not statistically different between the patients with mild and severe OM.