Located on Xq22, the gene associated with DDON syndrome, TIMM8A (originally called DDP for deafness–dystonia peptide; OMIM#300356) encodes a small protein that localizes to the intermembrane space in mitochondria (Jin et al., 1996; Tranebjaerg et al., 1995). This evidence concerns the gene TIMM8A and deafness dystonia syndrome.