BackgroundFanconi anemia (FA) is an inherited bone marrow failure syndrome associated with congenital abnormalities and hypersensitivity to DNA cross-linking agents. The high frequency of chromosomal breaks in FA lymphocytes has been related to the increased oxidative damage shown by these cells. Reactive oxygen species (ROS) are derived from the metabolism of molecular oxygen. It is now assumed that ROS are involved both in the initiation and in the progression of cancer. Antioxidants have the ability to transform ROS into stable and harmless compounds. Astaxanthin is a natural source of antioxidant; its effect might protect cells from oxidative damage. Its antioxidant activity is far higher than that of vitamin E. Aim of workThis study was designed to compare between the antioxidant effect of both astaxanthin and vitamin E as measured by their ability to reduce the frequency of induced chromosomal breakage in patients with FA. Participants and methodsThe current study included 15 patients with FA, nine females and six males, ranging in age from 4 to 21 years. The diagnosis of FA was confirmed by induction of chromosomal breakage by diepoxybutane. Astaxanthin and vitamin E were added at the start of the peripheral blood lymphocyte cultures to provide the possibility to improve the pro-oxidant state of the cells; then caffeine was added during the last 6 h of culture to induce chromosomal breakage. Results and conclusionThe level of breakage was markedly reduced using astaxanthin and vitamin E; however, there was no significant difference between the effects of both substances. Astaxanthin was found in a wide diversity of natural sources; also, it is 10 times more potent than vitamin A and much safer than vitamin E. Our study is the first to investigate the effect of astaxanthin on chromosomal breakage in vitro. We conclude that the administration could be beneficial for patients with FA to improve their hematopoietic state.