The formamidopyrimidine DNA glycosylase (FPG) alkaline comet assay, also known as the formamidopyrimidine DNA glycosylase (FPG) comet assay, is a laboratory technique used to assess DNA damage in individual cells. This assay is particularly useful for detecting oxidative DNA damage, which is caused by reactive oxygen species (ROS) such as hydroxyl radicals, superoxide anions, and hydrogen peroxide. The alkaline comet assay detects single- and double-stranded DNA breaks. An additional step involves treating the DNA with FPG enzyme, a DNA glycosylase specifically recognizes and removes oxidized purine, such as 8-oxoguanine and formamidopyrimidine. If oxidative damage is present in the DNA, the FPG treatment induces strand cleavage at the sites of modified bases. The resulting comet-like images are analyzed using specialized software. The comet tail length and intensity are quantified to determine the extent of DNA damage. The FPG alkaline comet assay provides valuable information about the extent of oxidative DNA damage in individual cells.