informative with respect to function. Chandler and colleagues (79) have created mice with a point mutation in the Arid domain and showed that the Arid domain in mice is critical for the function of the protein, yet mutations in the human gene are not especially localized to the Arid domain. Thus far, the Arid domain mutant mice do not have a higher incidence of cancer. Several frameshift mutations occur near the end of the protein, suggesting a critical function for the C terminus of the protein. The function of this subunit is unclear, but one report indicated that it could behave as a ubiquitin ligase (80). A murine mutation near the N terminus of BAF250a leads to alternative splicing and the production of a protein that induces hematopoietic proliferation in a non–cell-autonomous manner (81).
