The protein encoded by this gene is a member of the SWI/SNF family of proteins. Members of this family have helicase and ATPase activities and are thought to regulate transcription of certain genes by altering the chromatin structure around those genes. The SMARCAL1 protein convert RPA-bound, single stranded DNA into double-stranded DNA, an enzyme activity termed "annealing helicase".[8] This activity is important for two cellular functions: replication fork reversal,[9] and R-loop unwinding.[10]
The encoded protein shows sequence similarity to the E. coli RNA polymerase-binding protein HepA. Mutations in this gene are a cause of Schimke immunoosseous dysplasia (SIOD), an autosomal recessive disorder with the diagnostic features of spondyloepiphyseal dysplasia, renal dysfunction, and T-cell immunodeficiency.[7]