A family with X-linked dystonia-deafness syndrome with a novel mutation of the DDP gene

Background: X-linked dystonia-deafness syndrome (DD) is characterized by early-onset deafness followed by progressive dystonia in adulthood. Only 4 families with the syndrome have been reported, and all were white. Objective: To describe the first nonwhite family with X-linked DDS, involving 5 affected males in 4 generations. Results: Clinical features of the family members, who were Japanese, were mostly consistent with reports of DDS in whites except for a lack of visual disturbances. Whereas microdeletions in the deafness-dystonia peptide (DDP) gene were found in 2 white DDS families, our patients showed a novel mutation (arg80ter) in exon 2 of the DDP gene. Conclusion: The existence of a DDS family of Japanese origin with a new kind of mutation in the DDP gene provides additional evidence that the DDP gene is a causative gene for X-linked DDS.