[Cytogenetics study of chromosomal instability in Fanconi anemia in Tunisia]

Cells of Fanconi anemia (FA) is characterized by cellular and chromosomal hypersensitivity to DNA cross-linking agents. We tested mitomycin C at 25 ng/mL, 40 ng/mL and diepoxybutane 0.1 μg/mL in order to select a reference technique in the diagnosis of AF. We also studied the mitotic segregation of sex chromosomes. Our study focused on 73 patients with aplastic anemia suspecting AF and also 17 healthy controls. Thus, the MMC 25 ng/mL with a sensitivity to detect AF cells. DEB, by contrast, showed better specificity. FISH study shows the presence of instability in the AF mitotic cells. The association for routine diagnosis of MMC 25 ng/mL and DEB 0.1 mcg/mL, and the search for a mitotic instability by FISH is the best way of cytogenetic diagnosis of AF.