Ube2w and ataxin-3 coordinately regulate the ubiquitin ligase CHIP.

The mechanisms by which ubiquitin ligases are regulated remain poorly understood. Here we describe a series of molecular events that coordinately regulate CHIP, a neuroprotective E3 implicated in protein quality control. Through their opposing activities, the initiator E2, Ube2w, and the specialized deubiquitinating enzyme (DUB), ataxin-3, participate in initiating, regulating, and terminating the CHIP ubiquitination cycle.

Role of sepiapterin reductase gene at the PARK3 locus in Parkinson's disease.

Sepiapterin reductase (SPR) gene is an enzyme which catalyses the final step of tetrahydrobiopterin synthesis (BH4) and was implicated in Parkinson's disease (PD) pathogenesis as a candidate gene for PARK3 locus. A number of studies yielded association of the PARK3 locus with PD, and SPR knockout mice were shown to display parkinsonian features. To evaluate the role of SPR gene polymorphisms in diverse populations in PD, we performed collaborative analyses in the Genetic Epidemiology of Parkinson Disease (GEO-PD) Consortium.

Recessively inherited parkinsonism: effect of ATP13A2 mutations on the clinical and neuroimaging phenotype.

Objective: To determine clinical features and to identify changes in brain structure and function in compound heterozygous and heterozygous ATP13A2 mutation carriers.

Design: Prospective multimodal clinical and neuroimaging study.

Setting: University of Lübeck, Lübeck, Germany.

The Machado-Joseph disease-associated mutant form of ataxin-3 regulates parkin ubiquitination and stability.

Machado-Joseph disease (MJD), the most common dominantly inherited ataxia worldwide, is caused by a polyglutamine (polyQ) expansion in the deubiquitinating (DUB) enzyme ataxin-3. Interestingly, MJD can present clinically with features of Parkinsonism. In this study, we identify parkin, an E3 ubiquitin-ligase responsible for a common familial form of Parkinson's disease, as a novel ataxin-3 binding partner.

Possible genetic heterogeneity of spinocerebellar ataxia linked to chromosome 15.

Autosomal dominant spinocerebellar ataxias (SCAs) are a clinically and genetically heterogeneous group of neurodegenerative disorders. We investigated an SCA family from Serbia of Roma ethnic origin; four affected and nine unaffected family members underwent a detailed neurological examination. The presenting symptom in all patients was gait unsteadiness in early adulthood.

A large-scale genetic association study to evaluate the contribution of Omi/HtrA2 (PARK13) to Parkinson's disease.

High-profile studies have provided conflicting results regarding the involvement of the Omi/HtrA2 gene in Parkinson's disease (PD) susceptibility. Therefore, we performed a large-scale analysis of the association of common Omi/HtrA2 variants in the Genetic Epidemiology of Parkinson's disease (GEO-PD) consortium. GEO-PD sites provided clinical and genetic data including affection status, gender, ethnicity, age at study, age at examination (all subjects); age at onset and family history of PD (patients).

ATP13A2 variants in early-onset Parkinson's disease patients and controls.

Four genes responsible for recessively inherited forms of Parkinson's disease (PD) have been identified, including the recently discovered ATP13A2 (PARK9) gene. Our objective was to investigate the role of this gene in a large cohort of PD patients and controls. We extensively screened all 29 exons of the ATP13A2 coding region in 112 patients with early-onset PD (EOPD; <40 years) of mostly European ethnic origin and of 55 controls.

Mutations in THAP1 (DYT6) and generalised dystonia with prominent spasmodic dysphonia: a genetic screening study.

Background: DYT6 is a primary, early-onset torsion dystonia; however, unlike in DYT1 dystonia, the symptoms of DYT6 dystonia frequently involve the craniocervical region. Recently, two mutations in THAP1, the gene that encodes THAP (thanatos-associated protein) domain-containing apoptosis-associated protein 1 (THAP1), have been identified as a cause of DYT6 dystonia.

Methods: We screened THAP1 by sequence analysis and quantitative real-time polymerase chain reaction (PCR) in 160 white patients of European ancestry who had dystonia with an early age at onset (n=64), generalised dystonia (n=35), a positive family history of dystonia (n=56), or facial or laryngeal dystonia.

Frequency of heterozygous Parkin mutations in healthy subjects: need for careful prospective follow-up examination of mutation carriers.

The role of single heterozygous mutations in the putatively recessive Parkin gene in Parkinson disease (PD) is a vividly debated issue, partly caused by the largely unknown frequency of these mutations in healthy individuals. We investigated mutations in all 12 Parkin exons in 356 controls from two European populations including individuals from South Tyrol and Germany. None of the controls carried a homozygous or compound heterozygous mutation.

Genetic association study of the P-type ATPase ATP13A2 in late-onset Parkinson's disease.

A role of ATP13A2 in early-onset Parkinsonism (EOP) has been proposed. Conversely, the contribution of this ATPase to late-onset Parkinson's disease (PD) remains unexplored. We therefore conducted a case-control association study in this age-of-onset group with PD.

LRRK2 and Parkin mutations in a family with parkinsonism-Lack of genotype-phenotype correlation.

Here we report the relationship between age at onset, clinical course and genotype in a family with combined LRRK2 G2019S and Parkin exon 2 deletions. In the combined mutation carriers the age at onset and clinical course was highly variable and not always younger than in the carriers of LRRK2 G2019S mutations alone.

Transcranial sonography findings in a large family with homozygous and heterozygous PINK1 mutations.

Objective: To investigate substantia nigra (SN) echogenicity in members of a family with homozygous and heterozygous PTEN induced kinase (PINK1) mutations with or without signs of Parkinson's disease (PD).

Methods: Transcranial sonography (TCS) was used to investigate 20 members of a family with PINK1 mutations, including four homozygous and 11 heterozygous mutation carriers and five individuals with no mutation. For comparison, a healthy control group of 18 subjects without a positive family history of PD (control group) and a healthy control group of 15 subjects with a positive family history of sporadic PD (relative group) were investigated.

Limbic and frontal cortical degeneration is associated with psychiatric symptoms in PINK1 mutation carriers.

Background: Mutations in the PINK1 gene can cause Parkinson's disease and are frequently associated with psychiatric symptoms that might even precede motor signs.

Methods: To determine whether specific gray matter degeneration of limbic and frontal structures might be liable to different psychiatric symptoms in PINK1 mutation carriers, observer-independent voxel-based morphometry was applied to high-resolution magnetic resonance images of 14 PINK1 mutation carriers from a large German family and 14 age- and gender-matched healthy control subjects.

Results: Psychiatric diagnoses in PINK1 mutation carriers comprised major depression without psychotic symptoms and schizophrenia-spectrum, panic, adjustment, and obsessive-compulsive personality disorders.

Myoclonus-dystonia: significance of large SGCE deletions.

Myoclonus-dystonia (M-D) is an autosomal-dominant movement disorder caused by mutations in SGCE. We investigated the frequency and type of SGCE mutations with emphasis on gene dosage alterations and explored the associated phenotypes. We tested 35 M-D index patients by multiplex ligation-dependent probe amplification (MLPA) and genomic sequencing.

Evidence for linkage of restless legs syndrome to chromosome 9p: are there two distinct loci?

Background: Restless legs syndrome (RLS) is a common sensory-motor disorder characterized by paresthesias and an intense urge to move the legs with a considerable familial aggregation. To date, no gene mutation has been found, but five gene loci have been mapped in primary RLS to chromosomes 12q, 14q, 9p, 2q, and 20p (RLS1 through 5).

Patients/methods: We identified a four-generational German RLS family with 37 family members including 15 affected cases.

MECP2 mutations in Serbian Rett syndrome patients.

Background: Rett syndrome is a severe neurodevelopmental X-linked dominant disorder affecting 1/15,000 girls worldwide. Eight years ago, the MECP2 gene was associated with the devastating clinical features observed in Rett syndrome patients.

Objectives: To investigate the spectrum and the frequency of MECP2 mutations in Serbian Rett syndrome patients.

Autosomal dominant myoclonus-dystonia and Tourette syndrome in a family without linkage to the SGCE gene.

Unlabelled: The objective of this study was to report clinical details and results of genetic testing for mutations in the epsilon-sarcoglycan (SGCE) gene, the Slit and Trk-like 1 (SLITRK1) gene and for linkage to the DYT15, DYT1, and DRD2 gene loci in a family with autosomal dominant myoclonus-dystonia (M-D) and Gilles de la Tourette syndrome (GTS). Fourteen family members, from three generations, underwent a detailed clinical assessment and donated DNA samples. The SGCE and the SLITRK1 gene were sequenced and investigated by gene dosage analysis in selected family members.

Rapid and reliable detection of exon rearrangements in various movement disorders genes by multiplex ligation-dependent probe amplification.

Because of the occurrence of different types of mutations, comprehensive genetic testing for Parkinson's disease (PD), dopa-responsive dystonia (DRD), and myoclonus-dystonia (M-D) should include screening for small sequence changes and for large exonic rearrangements in disease-associated genes. In diagnostic and research settings, the latter is frequently omitted or performed by laborious and expensive quantitative real-time PCR (qPCR). Our study aimed to evaluate the utility of a novel method, multiplex ligation-dependent probe amplification (MLPA), in molecular diagnostics of movement disorders.

Co-occurrence of affective and schizophrenia spectrum disorders with PINK1 mutations.

Objective: To investigate a possible association of mutations in the PTEN-induced putative kinase 1 (PINK1) gene with psychiatric disorders in a large family with monogenic parkinsonism.

Method: 20 members of a family (4 homozygous, 11 heterozygous and 5 non-mutation carriers) were investigated for the presence of psychiatric disorders using the structured clinical interview for Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV); information on three additional heterozygous mutation carriers was obtained according to the family history research diagnostic criteria.

Results: We found predominantly affective and schizophrenia spectrum disorders in 11 (61%) of the 18 mutation carriers and in 1 (20%) of the 5 mutation-negative cases.

Intrafamilial phenotypic and genetic heterogeneity of dystonia.

Most cases of early-onset primary torsion dystonia are caused by the same 3-bp (GAG) deletion in the DYT1 gene. We describe a large Serbian family with significant intrafamilial variability of the DYT1 phenotype, from asymptomatic carrier status to late-onset focal, and generalized jerky dystonia. Seven mutation carriers (six proven by direct analysis and one by inferred haplotype) were identified, but only two of them were affected by dystonia (penetrance reduced to 29%).

Phenotypic spectrum of PINK1-associated parkinsonism in 15 mutation carriers from 1 family.

The phenotypic spectrum of PINK1-associated Parkinsonism was studied in a family with homozygous (n = 4) or heterozygous (n = 3) PINK1 mutations. All homozygous mutation carriers were definitely affected; the heterozygous carriers were asymptomatic but displayed unequivocal signs of probable or possible Parkinsonism. This finding suggests a role not only of homozygous but also of heterozygous PINK1 mutations in the development of parkinsonian signs and underlines the necessity to carefully investigate family members of affected mutation carriers.