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O Bandmann

Publications and source records attributed to O Bandmann.

At least 37 records · Page 2Linked to original sources

Dopa-responsive dystonia: a clinical and molecular genetic study.

We have studied the GTP-cyclohydrolase 1 (GCH-1) gene in 30 patients with the diagnosis of clinically definite (n = 20) or possible (n = 10) dopa-responsive dystonia (DRD) as well as in a child with atypical phenylketonuria due to complete GCH-1 deficiency. A large number of new heterozygote mutations (seven point mutations, two splice site mutations, and one deletion) as well as a new homozygote mutation in the child with atypical phenylketonuria were detected. In addition, two previously described mutations were found in two other cases. We further extended our investigation of GCH-1 to the 5' and 3' regulatory regions and report the first detection of point mutations in the 5' untranslated region. Demethylation of CpG islands does not appear to be an important causative factor for the GCH-1 mutations in DRD. In addition, we have extended the clinical phenotype of genetically proven DRD to focal dystonia, dystonia with relapsing and remitting course, and DRD with onset in the first week of life. None of our DRD patients without a mutation in GCH-1 had the 3-bp deletion recently detected in DYT1, the causative gene for idiopathic torsion dystonia with linkage to 9q34.

5' Untranslated Regions↗

Association of slow acetylator genotype for N-acetyltransferase 2 with familial Parkinson's disease.

BACKGROUND: Epidemiological studies have identified positive family history and exposure to environmental toxins as risk factors for Parkinson's disease (PD). An inherited defect of xenobiotic metabolism could result in increased susceptibility to such toxins. We investigated the frequency of functionally relevant polymorphisms in six detoxification enzymes among patients with PD to elucidate the relation between these polymorphisms and the disease. METHODS: We obtained brain-tissue samples from 100 patients with apparently sporadic PD and blood samples from 100 living patients with familial PD. For the control group, we extracted DNA from the tissue of 100 pathologically normal brains. The six enzymes analysed in these three groups were: CYP2D6, CYP2E1, NAD(P)H-menadione reductase, glutathione transferases M1 and T1, and N-acetyltransferase 2. We also investigated N-acetyltransferase 2 in 100 blood samples from patients with genetically proven Huntington's disease. We used PCR-based methods and restriction-enzyme analysis to detect polymorphisms. FINDINGS: The slow acetylator genotype for N-acetyltransferase 2 was more common in the familial PD group (69%) than in all controls (37%). Even after correction for multiple comparisons, this result remained highly significant (p = 0.002) for familial PD compared with normal controls (odds ratio 3.79 [95% CI 2.08-6.90]) and compared with Huntington's disease (2.45 [1.37-4.38], p = 0.004). The slow acetylator frequency for N-acetyltransferase 2 for sporadic PD was between that for Huntington's disease and familial PD. The frequencies of all the other polymorphisms were similar in the two study groups and the normal control group. INTERPRETATION: We found an association between the slow acetylator genotype for N-acetyltransferase 2 and familial PD. Further studies are needed to investigate the biological relevance of these findings, but slow acetylation could lead to impaired ability of patients with familial PD to handle neurotoxic substances.

Acetylation↗

Mitochondrial DNA polymorphisms in pathologically proven Parkinson's disease.

To date, five single base pair changes of the mitochondrial DNA have been reported to occur either exclusively or with increased frequency in Caucasian patients with Parkinson's disease (PD) and it has been postulated that these mutations might be casually related to the observed inhibition of mitochondrial respiratory chain function in PD. To evaluate these findings, we analysed the frequency of all five polymorphisms in 100 cases of pathologically proven cases of PD. We were either unable to detect the previously described polymorphisms in our series or found them to be present with the same frequency among controls. Our data do not support the hypothesis of an involvement of the mitochondrial DNA in the pathogenesis of PD.

Adult↗

GTP cyclohydrolase I mutations in patients with dystonia responsive to anticholinergic drugs.

OBJECTIVES: To investigate the hypothesis that GTP cyclohydrolase I (GCH1) mutations are responsible for the phenotype of highly anticholinergic responsive dystonia in patients with apparent primary torsion dystonia. METHODS: From 107 British patients with clinically diagnosed primary torsion dystonia, seven patients were identified with an excellent response to anticholinergic drugs. All six exons of the GCH1 gene were sequenced in these patients to identify mutations. RESULTS: Three novel GCH1 mutations were identified in two patients. One patient was a compound heterozygote with asymptomatic carrier parents. The clinical phenotype of patients with and without GCH1 mutations was similar. CONCLUSIONS: These findings show that a proportion of patients with apparent primary torsion dystonia and a good response to anticholinergic drugs have GCH1 mutations and therefore have a variant of dopa responsive dystonia. The difficulty in distinguishing clinically between patients with and without mutations underscores the importance of considering the diagnosis of a levodopa responsive dystonia in all such patients.

Adult↗

Multiple-system atrophy is genetically distinct from identified inherited causes of spinocerebellar degeneration.

Multiple system atrophy (MSA) is a neurodegenerative disorder of unknown cause. The only case-control study conducted in MSA patients to date suggested a possible contributory genetic component in the pathogenesis of this disorder. The aim of this study was to evaluate a possible overlap between clinically or pathologically well-defined MSA and other conditions with an identified genetic defect causing spinocerebellar degeneration in humans or mutant mice strains. The spinocerebellar ataxia type 1 and 3 genes (SCA1 and SCA3) were analyzed for a pathologic expansion in 80 patients with MSA to evaluate a possible overlap between MSA and SCA1 or SCA3. Weaver mice and lurcher mice are animal models for spinocerebellar degeneration; both share pathologic features with MSA. We sequenced the H5 pore region of the human homologue of the weaver mouse gene, hiGIRK2, in all our patients. In lurcher mice, previous biochemical studies have shown a decreased intracellular response to insulin-like growth factor 1 (IGF-1) in the cerebellar cortex, and we thus investigated the possibility of an allelic association between MSA and the receptor for IGF-1. In addition, we evaluated a possible involvement of the ciliary neurotrophic factor gene (CNTF) and examined the role of HLA-A32 to clarify the conflicting data from previous studies. No changes were detected in any of the analyzed genes. Our studies strongly suggest that MSA is an autonomous syndrome distinct from identified genetic causes for spinocerebellar degeneration.

Alleles↗

The GTP-cyclohydrolase I gene in atypical parkinsonian patients: a clinico-genetic study.

GTP cyclohydrolase I (GTPCH) has recently been identified as the first causative gene for Dopa-responsive dystonia (DRD). DRD typically presents with dystonia in the lower limbs in childhood, but may produce an akinetic-rigid syndrome in middle and old age. We have sequenced the GTPCH gene in 29 Parkinsonian patients without a positive family history for DRD, but who shared at least one feature of the akinetic-rigid presentation of DRD: 23 patients had at least one living relative who also suffered from an akinetic-rigid syndrome; 2 patients had an abnormally mild course of their parkinsonism which was extremely dopa-responsive. DNA was also analysed from 4 brain samples of patients who were clinically diagnosed as suffering from Parkinson's disease, but then did not show any pathological findings at post mortem. No changes in the sequence of the GTPCH gene were detected. We conclude that so far there is no evidence that mutations of the GTPCH gene are responsible for the development of parkinsonism in patients without a positive family history of DRD.

Aged↗

The human homologue of the weaver mouse gene in familial and sporadic Parkinson's disease.

The pathological hallmark of Parkinson's disease is cell death of dopaminergic neurons in the substantia nigra, resulting in striatal dopaminergic deficit and a clinical syndrome dominated by disorders of movement. The cause for this cell loss is unknown, but the possibility of a contributing genetic factor is increasingly recognized. Homozygous weaver mice, a mutant mouse strain, display progressive postnatal depletion of dopaminergic cells in the mesencephalon and have thus been proposed as an animal model for Parkinson's disease. Recently, mGIRK2, a putative G-protein inward rectifier K+ channel, has been identified as the causative gene in the weaver mouse and a homozygous mutation has been described in the H5 pore region of this channel. The human homologue of mGIRK2, KCNJ7 or hiGIRK2, has previously been isolated on chromosome 21q22.1. A possible involvement of this gene in the pathogenesis of Parkinson's disease has been discussed. To evaluate the possibility of a shared genetic defect in weaver mouse and Parkinson's disease, we analysed the H5 pore region of hiGIRK2 in familial and sporadic cases of Parkinson's disease. The sequence was normal in all cases examined, suggesting a differing aetiology of nigral cell loss in Parkinson's disease and weaver mice.

Animals↗

Dopa-responsive dystonia in British patients: new mutations of the GTP-cyclohydrolase I gene and evidence for genetic heterogeneity.

Dopa-responsive dystonia (DRD) was originally described in a series of Japanese patients, but is now increasingly recognized in other countries. Recently the GTP cyclohydrolase I (GTPCH) gene was isolated as the first causative gene for dopa-responsive dystonia (DRD). Mutations were identified in three Japanese families with autosomal dominantly inherited DRD and in one sporadic Japanese patient. Characterisation of the exon-intron boundaries of this gene has now allowed the analysis of mutations at the level of genomic DNA. Amplifying all six exons, we analyzed the GTPCH gene in nine British families with 33 affected family members and in three sporadic cases and found six new mutations. Only point mutations were found, causing a stop codon in one family and an amino acid change in highly conserved regions of the gene in a further four families and in one sporadic case. None of these mutations were detected more than once and none of the mutations previously described were found in our patients. No mutations were identified in four families and in two sporadic cases.

Dopamine Agents↗

Signal changes on MRI and increases in reactive microgliosis, astrogliosis, and iron in the putamen of two patients with multiple system atrophy.

A correlation of clinical, MRI, and neuropathological data is reported in two patients with multiple system atrophy (MSA). On MRI, patient 1 showed striatal atrophy, reduction of T2 relaxation times within most of the putamen, and a band of hyperintense signal changes in the lateral putamen. In patient 2, MRI disclosed only shortening of the T2 signal in the putamen. Immunohistochemistry showed pronounced reactive microgliosis and astrogliosis in the affected brain regions. In patient 1, the area with the most pronounced microgliosis and astrogliosis most likely correlated with the area of hyperintense signal changes on MRI. This area also contained the highest amount of ferric iron, which was increased in the putamen of patient 1 but not patient 2. It is unlikely that the hypointense signal changes in the putamen are due to an increase of iron alone. Reactive microglial and astroglial cells may play a part in the pathogenesis of MSA.

Adult↗

CYP2D6-debrisoquine hydroxylase gene polymorphism in multiple system atrophy.

Molecular genetic studies of the cytochrome P450 system enzyme CYP2D6, which hydroxylates debrisoquine, have indicated an excess of mutant alleles in large series of patients with Parkinson's disease (PD) when compared with controls. We have investigated CYP2D6 polymorphism in 91 patients with multiple system atrophy (MSA) in order to determine if this finding is specific to PD or if there is similar evidence of genetic susceptibility to neurotoxicity in MSA. The distribution of CYP2D6 alleles was not significantly different between MSA patients and controls, and there were fewer poor metabolisers in the MSA group than in the control group.

Alleles↗

Sequence of the superoxide dismutase 1 (SOD 1) gene in familial Parkinson's disease.

Mutations in the superoxide dismutase 1 (SOD1) gene have been detected in affected members of some families with familial amyotrophic lateral sclerosis. To evaluate the possibility of a shared genetic defect in amyotrophic lateral sclerosis and Parkinson's disease, the SOD1 gene was sequenced in index patients with familial Parkinson's disease from 23 families. No changes were detected.

Amyotrophic Lateral Sclerosis↗

Epidemiological, genetic, pharmacological, kinesiological, nuclear medical (IBZM-SPECT), standard and functional MRI studies on Parkinson's disease and related disorders and economic evaluation of Parkinson's disease therapy--clinical projects in the BMFT-research program Munich: "Parkinson's disease and other basal ganglia disorders".

The results of selected clinical research projects related to epidemiological, genetic, pharmacological, kinesiological, and neuroimaging aspects (SPECT, PET, MRI, functional MRI) of basal ganglia disorders such as Parkinson's disease, Progressive Supranuclear Palsy, Multiple System Atrophy and Wilson's disease are summarized. A retrospective pharmacoeconomic analysis of Parkinson's disease is presented. These studies are part of a nationwide research program of the German ministry of research and technology (BMFT) entitled "Parkinson's disease and other basal ganglia disorders" and were carried out at the Department of Neurology, LMU München.

Basal Ganglia Diseases↗

Apo E genotypes in multiple sclerosis, Parkinson's disease, schwannomas and late-onset Alzheimer's disease.

Apolipoprotein E (apo E) exists in three allelic, functionally distinct isoforms (apo E2, E3 and E4). Recent work has suggested that apo-E-dependent uptake of lipoproteins may play important roles in the development and maintenance of the nervous system and in the responses to both peripheral and central nervous system injury. If apo-E-mediated transport of lipids were a rate-limiting step in these processes, one might expect that the functional differences between the alleles would be associated with varying predispositions to neurodegenerative and demyelinating diseases. Thus, we looked for an association between particular apo E genotypes and susceptibility to multiple sclerosis and Parkinson's disease. If apo-E-mediated cholesterol uptake were limiting in neuronal growth, one might also expect that apo E2 alleles would slow CNS tumour growth. Accordingly, apo E genotypes were investigated in individuals with sporadic vestibular schwannomas and neurofibromatosis type 2 (NF-2). No significant alteration in the apo E allele distributions was observed in any of these conditions, nor did the apo E genotypes correlate with disease severity. However, we confirmed the previous findings of an over-representation of the apo E4 allele in autopsy-diagnosed late-onset Alzheimer's disease patients. In addition, our data supported the recent observations that apo E2 may be associated with a protective effect for late-onset Alzheimer's disease. These contrasting risks associated with the apo E2 and E4 alleles strengthen the suggestions that this gene is directly involved in the pathogenesis of Alzheimer's disease.

Alzheimer Disease↗