SOX-13 is a HMG box transcription factor that binds to the sequence 5'-AACAAT-3' [, ]. It represses Wnt/TCF signaling by interacting with TCF1. It also interacts with Hhex (hematopoietically expressed homeobox), and this interaction displaces SOX13 from the SOX13 x TCF1 complex [].In humans, SOX-13 is an islet cell autoantigen (ICA12). Antibodies to SOX-13 are associated with type 1 diabetes [].