DNA-dependent ATPase and 5' to 3' DNA helicase required for the maintenance of chromosomal stability. Acts late in the 'Fanconi anemia' pathway of DNA repair, after FANCD2 ubiquitination. Probably not involved in the repair of DNA double-strand breaks by homologous recombination. ATP + H2O = ADP + H(+) + phosphate Binds 1 [4Fe-4S] cluster. Belongs to the DEAD box helicase family. DEAH subfamily.