Human SMARCAL1, an annealing helicase that has role both in DNA damage response as well as transcription regulation, has been linked to Schimke Immuno-Osseous Dysplasia (SIOD) and analysis of three mutations, which map to RecA-like domain 1, present in these patients showed that these mutants cannot hydrolyze ATP [26–30]. This evidence concerns the gene SMARCAL1 and Schimke immuno-osseous dysplasia.