Studying Homologous Recombination in Fanconi Anemia

Cells from patients suffering from the recessive syndrome Fanconi anemia (FA), are characterized by increased sensitivity to agents that induce DNA interstrand cross-links (ICLs). This hypersensitivity manifests as a dramatically elevated rate of chromosome breaks in FA cells when compared to controls and led, more than thirty years ago, to the suggestion that the repair of ICLs is disturbed in FA. Today, a DNA repair defect as the basis of FA is widely accepted, however, the exact role of the 12 known genes is still elusive. The past several years have brought growing evidence that FA cells are compromised in homology dependent DNA repair processes. This review will summarize these studies with a focus on integrated plasmid reporter assays which are used to investigate repair products after induction of a single defined DNA double-strand break (DSB).