X-linked dystonia-parkinsonism (XDP; OMIM314250), also referred to as DYT3dystonia or "Lubag" disease, was first described as an endemic disease in the Philippine island of Panay.
Other entities entailing dystonia-parkinsonism include dopamine transporter deficiency syndrome (SLC63 mutations); dopa-responsive dystonias; young-onset parkinsonism (PARKIN, PINK1 and DJ-1 mutations); PRKRA mutations; and X-linked TAF1 mutations, which rarely can also manifest in women.
Some cases of primary and neurodegenerative dystonia have been associated with mutations in individual genes critical to the G1-S checkpoint pathway (THAP1, ATM, CIZ1 and TAF1).
Inherited dystonia designated by DYT locus symbols can be separated into three broad phenotypic categories: primary torsion dystonia (PTD), where dystonia is the only clinical sign (except for tremor) (DYT1, 2, 4, 6, 7, 13, 17, and 21); dystonia plus loci, where other phenotypes in addition to dystonia, including parkinsonism or myoclonus, are present (DYT3, 5/14, 11, 12, 15, and 16); and paroxysmal forms of dystonia/dyskinesia (DYT8, 9, 10, 18, 19, and 20).
THAP1 is the first transcriptional factor involved in primary dystonia and the hypothesis of a transcriptional deregulation, which was primarily proposed for the X-linked dystonia-parkinsonism (DYT3dystonia), provided thus a new way to investigate the possible mechanism underlying the development of dystonic movements.
Because the clinical presentation of patients with XDP resembles that of patients with Parkinson disease or dystonia, it is reasonable to predict the neuropsychological profile might be similar; however, the neuropsychological profile of a XDP patient has not previously been published.