| Domain | Key facts | Evidence type | Key citations |
|---|---|---|---|
| Identifiers | X-linked dystonia-parkinsonism (XDP); synonyms: DYT/PARK-TAF1, DYT3, Lubag; OMIM #314250; adult-onset X-linked neurodegenerative movement disorder, endemic in the Philippines/Panay founder population | Review | (pqac-00000000, pqac-00000001) |
| Genetics | Causal lesion is a ~2.6 kb SINE-VNTR-Alu (SVA) retrotransposon inserted in intron 32 of **TAF1** on Xq13.1; all probands share a founder haplotype around TAF1; CRISPR excision of the SVA restores TAF1 mRNA in model cells | Review + primary | (pqac-00000001, pqac-00000021, pqac-00000023) |
| Repeat feature | The pathogenic SVA contains a polymorphic hexameric **(CCCTCT)n** repeat; typical reported range ~30–55 repeats, with amplified HEX tract compared with typical SVAs; repeat length inversely correlates with age at onset and age at death | Review + primary | (pqac-00000003, pqac-00000007, pqac-00000017, pqac-00000023) |
| Modifiers | Each additional hexamer repeat shortens age at onset by ~1.4 years in larger cohorts; repeat length explained ~50% of age-at-onset variance initially, and repeat plus known modifiers explain only ~65%, implying additional factors | Review | (pqac-00000022, pqac-00000006) |
| DNA repair modifiers | **MSH3** and **PMS2** modify age-associated penetrance/expressivity; protective alleles delay onset; findings link XDP to repeat-instability biology shared with Huntington disease | Review + primary | (pqac-00000000, pqac-00000007, pqac-00000016, pqac-00000023) |
| Inheritance / penetrance | X-linked recessive; predominantly affects Filipino males; rare affected females occur via homozygosity, skewed X-inactivation, or aneuploidy; penetrance is age-dependent | Review | (pqac-00000000, pqac-00000016) |
| Epidemiology | Endemic on Panay island, Philippines; reported prevalence ~5.74 per 100,000 in Panay; strong founder effect with indigenous Philippine haplotype | Review + primary summary | (pqac-00000001, pqac-00000002) |
| Age at onset | Median/average onset ~39–40 years; reported onset range 20–67 years; disease is chronic, progressive, and fatal | Review + primary | (pqac-00000000, pqac-00000007, pqac-00000017) |
| Core clinical phenotype | >80% present with focal dystonia; dystonia is initial feature in ~93% in some series; onset distribution ~60% craniocervical, ~37% limb, ~4% truncal; dystonia typically generalizes within 5 years (5–10 years in some reviews), then parkinsonism may emerge and later predominate | Review | (pqac-00000000, pqac-00000001, pqac-00000017) |
| Morbidity / outcome | Severe disability is common; aspiration contributes to premature death; mean age at death reported ~55.6 years; no obvious correlation between repeat length and disease duration in one primary study | Review + primary | (pqac-00000001, pqac-00000007, pqac-00000017) |
| Neuropathology | Preferential degeneration of striatal medium spiny neurons with caudate/putaminal atrophy; iron accumulation in anteromedial putamen reported; subventricular zone neural progenitor loss also described | Review + primary/review | (pqac-00000001, pqac-00000017, pqac-00000020) |
| Molecular mechanism: TAF1 | XDP SVA is associated with reduced/aberrant **TAF1** expression, altered splicing, partial intron 32 retention, and disease-associated transcript **TAF1-32i** from cryptic exon 32i that disrupts the ORF and can trigger nonsense-mediated decay | Review + primary | (pqac-00000002, pqac-00000018, pqac-00000020) |
| Mechanism: G-quadruplexes | G-rich XDP SVA sequences form stable G-quadruplexes in vitro and in patient fibroblasts/NPCs; G4 stabilization (BRACO-19, quarfloxin) reduces downstream TAF1 transcripts and increases upstream transcripts, while G4 destabilization (PhpC) increases TAF1 transcripts | Primary | (pqac-00000003) |
| Mechanism: epigenetic repression | **ZNF91** binds SVAs and, with TRIM28, helps establish local mini-heterochromatin marked by **H3K9me3** and DNA methylation; removing this repression worsens the XDP molecular phenotype, increasing TAF1 intron retention and reducing TAF1 expression | Primary | (pqac-00000008, pqac-00000010) |
| Mechanism: aging modifier | ZNF91 expression declines with age in brain/blood; reported associations include frontal cortex dR2 = -0.10354 (P = 2.02E-06), cerebellum dR2 = -0.0484 (P = 5.79E-04), nucleus accumbens dR2 = -0.05257 (P = 0.0003); this may help explain late onset | Primary | (pqac-00000011, pqac-00000013) |
| Somatic instability | Repeat instability is expansion-biased, length-dependent, and tissue-specific; brain shows greater expansion than blood; cortical regions show relatively high instability, cerebellum low instability; observed changes range from small shifts (up to ±5 repeats) to rarer large expansions (~20 to >100 repeats) and contractions (~20–40 repeats) | Primary | (pqac-00000007) |
| Molecular profiling | Proteomics in patient-derived striatal neurons/MSNs shows altered RNA metabolism, splicing, mitochondrial pathways, chromatin assembly, and overlap with neurodegeneration networks; TAF1, YY1, ATF2, USF1, and MYC emerged as enriched regulators | Primary | (pqac-00000002, pqac-00000020) |
| Biomarkers | Disease-specific TAF1 intron-retention / TAF1-32i transcripts are candidate molecular biomarkers; reviews also cite neurofilament light chain as a proposed biomarker direction, but validated clinical biomarker use remains limited | Review + primary | (pqac-00000018, pqac-00000023, pqac-00000001) |
| Diagnostics | Diagnosis integrates characteristic phenotype, Panay/Filipino ancestry or family history, and confirmatory genetic testing for the TAF1 intron 32 SVA insertion/associated haplotype; repeat sizing and long-read/nanopore approaches are relevant for research and may aid molecular characterization | Review | (pqac-00000000, pqac-00000004, pqac-00000017) |
| Intervention landscape | Current care is largely symptomatic/supportive; mechanistically motivated experimental avenues include SVA excision, splicing correction, G4 destabilization, and modulation of epigenetic repressors/TAF1 expression | Review + primary | (pqac-00000003, pqac-00000018, pqac-00000023) |
| Trial: focused ultrasound | **NCT05592028**: MR-guided focused ultrasound pallidothalamic tractotomy, expanded access, AVAILABLE; adult genetically confirmed male XDP; outcomes include XDP-MDSP scale, XDP clinical/functional staging, BFMDRS, UPDRS with follow-up to 12 months | Clinical trial registry | (pqac-00000024) |
| Trial: nutritional support | **NCT03019458**: MINGO supplement trial, randomized open-label, COMPLETED, n = 50; intervention = moringa/rice/mung-bean supplement for 12 weeks; primary endpoint = BMI; secondary endpoints = mortality, infectious-cause hospitalizations, MUAC | Clinical trial registry | (pqac-00000025) |
| Trial: sensorimotor / DBS assessment | **NCT05713721**: observational sensorimotor integration study including DYT/PARK-TAF1 carriers; evaluates TMS short-latency afferent inhibition, video-based clinical outcomes, and effects of deep brain stimulation on/off in symptomatic participants | Clinical trial registry | (pqac-00000026, pqac-00000027) |


*Table: This table condenses the main structured facts about X-linked dystonia-parkinsonism across identifiers, genetics, modifiers, epidemiology, clinical features, mechanisms, biomarkers, and current trial activity. It is designed to support rapid knowledge-base population while preserving traceability to the gathered evidence.*