RT Journal Article SR Electronic T1 Schimke immuno-osseous dysplasia: SMARCAL1 loss-of-function and phenotypic correlation JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP 49 OP 59 DO 10.1136/jmg.2008.060095 VO 46 IS 1 A1 Elizondo, L I A1 Cho, K S A1 Zhang, W A1 Yan, J A1 Huang, C A1 Huang, Y A1 Choi, K A1 Sloan, E A A1 Deguchi, K A1 Lou, S A1 Baradaran-Heravi, A A1 Takashima, H A1 Lücke, T A1 Quiocho, F A A1 Boerkoel, C F YR 2009 UL http://jmg.bmj.com/content/46/1/49.abstract AB Background: Schimke immuno-osseous dysplasia (SIOD) is an autosomal recessive pleiotropic disorder caused by mutations in SMARCAL1. SMARCAL1 encodes an enzyme with homology to the SNF2 chromatin remodelling proteins.Methods: To assess the affect of SMARCAL1 mutations associated with SIOD on SMARCAL1 expression and function, we characterised the effects of various mutations on mRNA and protein expression in patient tissues and cell lines, and the ATPase activity, subcellular localisation, and chromatin binding of SMARCAL1 missense mutants.Results: The SIOD associated SMARCAL1 mutations affected SMARCAL1 protein expression, stability, subcellular localisation, chromatin binding, and enzymatic activity. Further, expressing SMARCAL1 missense mutants in Drosophila melanogaster showed that disease severity was inversely proportionate to overall SMARCAL1 activity.Conclusion: Our results show for the first time that SMARCAL1 binds chromatin in vivo and that SIOD arises from impairment of diverse SMARCAL1 functions.