Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The literature regarding parkinsonism of early-onset indicates that it encompasses several diseases differing in their clinical and pathological features. Since 1968 we have reported cases of early-onset parkinsonism with diurnal fluctuation of symptoms (abbrev. as EPDF). Attention has been focused on its similarities to or differences from Parkinson's disease (PD), juvenile parkinsonism of Yokochi, and hereditary progressive dystonia (HPD) of Segawa et al. In this paper we report the clinical and pathological characteristics of EPDF to facilitate its nosological identification. We examined the pathological features of EPDF in two cases. Case 1 was a 52-year-old female with consanguineously related parents and two other affected sisters. The disease began at the age of 20, and she had marked diurnal fluctuation of symptoms. With the assistance of L-dopa and bromocriptine, she was able to enjoy relatively satisfactory daily life activity until the age of 50. In the last two years she was bed-ridden with advanced parkinsonism. Case 2 was a 56-year-old man without any contributing family history. His disease started at age 26 and his symptoms showed slight fluctuation during the earlier stages of the disease. Treatment with L-dopa and bromocriptine was associated with marked up-and-down phenomenon and choreatic dyskinesia. Pathological study in the two cases revealed marked cell loss in the substantia nigra zona compacta, especially in the area A9, while the neuronal cell population of the ventral tegmental area (A10), locus caeruleus, superior raphae nucleus, and substantia innominata was relatively well preserved. There were no Lewy bodies.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Early-onset parkinsonism with diurnal fluctuation--clinical and pathological studies]. 836 54

Among heterogeneous diseases manifested by parkinsonism beginning early in life, there is a disease presenting with marked diurnal fluctuation of symptoms, called autosomal recessive early-onset parkinsonism with diurnal fluctuation (AR-EPDF). To identify the characteristics of this condition as a disease entity, we examined the clinical manifestations of AR-EPDF patients (Group I, n = 42) in comparison with those of early-onset parkinsonism patients without diurnal fluctuation (Group II, n = 34). Family history suggesting autosomal recessive inheritance was noted in 85.7% of Group I patients and 17.6% of Group II. The male-to-female ratio was 1: 1.8 in Group I, and 1:0.89 in Group II. Age at onset showed a standard distribution with an average of 25.6 years (SD: +/- 7.7) in Group I and an average of 32.7 with an increasing pattern toward 40 years in Group II. The initial symptom was dystonic gait disturbance in 42.9% of Group I and 5.9% of Group II, parkinsonian gait in 19.9% of Group I and 2.9% of Group II, and tremor in 28.6% of Group I and 41.2% of Group II. The main clinical feature was parkinsonism in both groups. Diurnal fluctuation of parkinsonism was remarkable in all but one (97.6%) of Group I, while it was not observed in Group II. Dystonic postures were noted in 79.4% of Group I and in 37.1% of Group II; hyperactive tendon reflexes in 74.3% of Group I patients and in 20% of Group II. Autonomic symptoms were mild in both groups. None of the Group I patients had dementia while two of Group II did. Levodopa was markedly effective in both groups. Dopa-induced dyskinesia was observed in 96.8% of Group I and in 61.8% of Group II. As for progression of the disease, the Hoehn-Yahr stage of patients on medication was evaluated as 2.2 +/- 0.7 (mean +/- SD) in Group I and 3.1 +/- 1.1 in Group II for a period of 10 to 20 years of onset, 2.5 +/- 0.8 in Group I and 3.3 +/- 0.5 in Group II for 20 to 30 years, and 3.2 +/- 0.9 in Group I and 4.3 +/- 0.6 in Group II after 30 years. There were significant differences between the two groups in the frequency of positive family history, in the mean and distribution of age at onset, in the incidence of dystonic gait as the initial symptom, and in the incidences and medians of the variables including dystonia, hyperreflexia and dopa-induced dyskinesia, as well as in the progression of the disease. Thus, we have successfully characterized the clinical features of AR-EPDF and demonstrated that diurnal fluctuation is a cardinal symptom of this disease. Reported pathologic studies on AR-EPDF showed the nigral lesion characterized by non-Lewy body type degeneration and the occurrence of melanin-poor neurons. These pathologic findings as well as the clinical manifestations differentiate AR-EPDF from Parkinson's disease and from autosomal-dominant familial parkinsonism. Low melanin-content of the nigral neurons is also a striking feature of hereditary progressive dystonia with diurnal fluctuation, in which unlike AR-EPDF there is no neuronal loss in the substantia nigra.
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PMID:[Autosomal recessive early-onset parkinsonism with diurnal fluctuation (AR-EPDF)--clinical characteristics]. 895 46

Autosomal recessive juvenile parkinsonism (AR-JP, PARK2; OMIM 602544), one of the monogenic forms of Parkinson's disease (PD), was initially described in Japan. It is characterized by early onset (before age 40), marked response to levodopa treatment and levodopa-induced dyskinesias. The gene responsible for AR-JP was recently identified and designated parkin. We have analysed the 12 coding exons of the parkin gene in 35 mostly European families with early onset autosomal recessive parkinsonism. In one family, a homozygous deletion of exon 4 could be demonstrated. By direct sequencing of the exons in the index patients of the remaining 34 families, eight previously undescribed point mutations (homozygous or heterozygous) were detected in eight families that included 20 patients. The mutations segregated with the disease in the families and were not detected on 110-166 control chromosomes. Four mutations caused truncation of the parkin protein. Three were frameshifts (202-203delAG, 255delA and 321-322insGT) and one a nonsense mutation (Trp453Stop). The other four were missense mutations (Lys161Asn, Arg256Cys, Arg275Trp and Thr415Asn) that probably affect amino acids that are important for the function of the parkin protein, since they result in the same phenotype as truncating mutations or homozygous exon deletions. Mean age at onset was 38 +/- 12 years, but onset up to age 58 was observed. Mutations in the parkin gene are therefore not invariably associated with early onset parkinsonism. In many patients, the phenotype is indistinguishable from that of idiopathic PD. This study has shown that a wide variety of different mutations in the parkin gene are a common cause of autosomal recessive parkinsonism in Europe and that different types of point mutations seem to be more frequently responsible for the disease phenotype than are deletions.
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PMID:A wide variety of mutations in the parkin gene are responsible for autosomal recessive parkinsonism in Europe. French Parkinson's Disease Genetics Study Group and the European Consortium on Genetic Susceptibility in Parkinson's Disease. 1007 23

We identified a PARK 2 (AR-JP) family with a patient presenting with homozygous deletion of D 6 S305--a marker within the 17cM region for PARK 2 locus. Markers surrounding D 6 S305 which are mapped 0 cM apart from D 6 S305, were not deleted, indicating that PARK 2 gene is located extremely close to D 6 S305. Exon search in the inserts with average size of 100 kb of BAC clones, which harbor D 6 S305, led us to find the exonic sequences which was subsequently proved to be exon 7 of the Parkin gene. From this exon sequences, full-length cDNA was isolated, and BAC contig covering Parkin gene was generated. Homozygous deletions or frame-shift mutations in the Parkin gene were found in the patients with AR-JP/PARK 2, revealing that a loss-of-function of Parkin gene is responsible for AR-JP/PARK 2. Our findings indicate that constant production of Parkin protein is essentially required for maintaining the survival of nigral neurons. One attractive hypothesis is that Parkinson's disease and AR-JP/PARK 2 might share a common effector pathway for nigral neuronal death. In this scenario, as PARK 2 is not accompanied with Lewy body formation. Parkin might act at or downstream of synuclein aggregation, which has been recently implicated as a trigger event for neuronal death in Parkinson's disease. In any case, identification of functional targets of Parkin protein will give us an important clue to identify downstream events of neuronal death which is activated by inclusion body formation.
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PMID:[A Parkin gene (PARK 2) and Parkinson's disease]. 1037 86

Parkin gene, which is one of the causes of familial Parkinson's disease, was cloned in 1998, and it was found that mutations of this gene induces familial Parkinson's disease of autosomal recessive form (AR-JP). Clinical studies have revealed that almost cases of AR-JP are consanguineous or hereditary. However, AR-JP may also be caused by marriage between two carriers. We therefore investigated the existence of a homozygous deletion in the parkin gene in 10 patients with juvenile Parkinson's disease with the onset of age younger than 40 years without consanguinity or heredity. A large delection of the gene was found in 2 of the 10 patients with sporadic Parkinson's disease, and both of these deletion were exon 4. The present study clearly suggests that juvenile Parkinson's disease in Japan may be caused by abnormalities in parkin gene regardless of family history or consanguinity.
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PMID:[Two cases of sporadic juvenile Parkinson's disease caused by homozygous deletion of Parkin gene]. 1065 3

In most patients with Parkinson's disease (PD), the contribution of genetic factors as well as environmental factors remains to be elucidated. But, it has become clear that genetic factors contribute to the pathogenesis of PD after identification of the distinct genetic loci for certain forms of familial PD. We recently identified the novel large gene "parkin" responsible for an autosomal recessive form of familial parkinsonism (AR-JP). AR-JP is a distinct clinical and genetic entity characterized by early onset before 40 years. Pathological changes in this form revealed selective degeneration of the pigmented neurons in the substantia nigra and locus coeruleus, but no Lewy bodies were found. The parkin gene encodes a novel protein of 465 amino acids. The parkin gene is mildly homologous to ubiquitin at the N-terminal portion and has a RING-finger motif at the C-terminal portion. We found variable different homozygous deletions involving exons 3, 4, 5, 3 to 4, 3 to 5, and 3 to 7 in AR-JP families from Japan. In addition to exonic deletions, we identified a one base deletion in exon 5 in two AR-JP families. Although we have identified several mutations in parkin gene, characterization of its gene product, "Parkin protein" has not yet been established. To elucidate the molecular mechanism underlying the disease, we have analyzed the subcellular localization of the Parkin protein by immunohistochemical and immunoblotting studies on patients with AR-JP and sporadic PD using two antibodies. Parkin protein was absent in all regions of the brains of AR-JP patients. Parkin protein was not decreased in brains of sporadic PD patients. Parkin protein was located in both Golgi complex and cytosol. Taken together, the Parkin protein may play a role in vesicular transport system in association with the Golgi complex.
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PMID:[Parkin gene and its function; a key to understand nigral degeneration]. 1079 Oct 92

Autosomal recessive early-onset parkinsonism with diurnal fluctuation (AR-EPDF, syn. autosomal recessive juvenile parkinsonism, PARK2) is one of the hereditary parkinsonian syndromes. We examined subjects consisting of 43 patients from 22 families with AR-EPDF. The clinical features were relatively homogeneous, including the average age at onset of 26.1 years, beginning with dystonic gait disturbance, diurnal fluctuation of the symptoms (sleep benefit) unrelated to medication, dystonia (mainly foot dystonia), hyperactive tendon reflex, remarkable effect of levodopa and other antiparkinsonism drugs, susceptibility to dopa-induced dyskinesia, mild autonomic symptoms, absence of dementia, and slow progression of disease. Some patients had hysteric character or psychic symptoms provoked by medication. Pathologic study revealed neuronal loss in the substantia nigra pars compacta and locus coeruleus without Lewy body formation. We performed extensive molecular genetic analysis of the parkin gene in 16 families to identify a total of six different deletional mutations. In AR-EPDF loss of newly discovered 'Parkin' protein is responsible for selective degeneration of the pigmented neurons in the substantia nigra and locus coeruleus. Compared with autosomal dominant Parkinson's disease, AR-EPDF appears to be more prevalent and present in several ethnic groups.
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PMID:Autosomal recessive early-onset parkinsonism with diurnal fluctuation: clinicopathologic characteristics and molecular genetic identification. 1098 66

The contribution of genetic factors to the pathogenesis of Parkinson's disease (PD) is supported by the demonstration of the high concordance in twins studies using positron emission tomography (PET), the increased risk among relatives of PD patients in case-control and family studies, and the existence of familial PD and parkinsonism by single gene defect. Recently several genes have been mapped and/or identified. Alpha-synuclein is involved in a rare dominant form of familial PD with dopa-responsive parkinsonism features and Lewy body-positive pathology. In contrast, parkin is responsible for the autosomal recessive form (AR-JP) of early onset PD with Lewy body-negative pathology. The clinical features of this form include early onset (in the 20s), levodopa-responsive parkinsonism, diurnal fluctuation, and slow progression of the disease. Parkin consists of 12 exons and the estimated size is over 1.5 Mb. To date, variable mutations such as deletions or point mutations resulting in missense and nonsense changes have been reported in AR-JP patients. In addition, the localization of parkin indicates that parkin may be involved in the axonal transport system. More recently we have found that parkin interacts with the ubiquitin-conjugating enzyme E2 and is functionally linked to the Ub-proteasome pathway as a ubiquitin ligase, E3. These findings fit the characteristics of a lack of Lewy bodies (these are cytoplasmic inclusions that are considered to be a pathological hallmark). Our findings should enhance the exploration of the mechanisms of neuronal death in PD as well as other neurodegenerative disorders of which variable inclusion bodies are observed.
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PMID:Autosomal recessive juvenile parkinsonism: a key to understanding nigral degeneration in sporadic Parkinson's disease. 1103 96

Mutations in the PARKIN gene are associated with early-onset (juvenile) Parkinson's disease. We analyzed the coding sequence of this gene (exons 1-12) in patients from a family with three affected siblings, born to first-degree consanguineous parents, with an onset before 23 years and foot dystonia as the initial clinical symptom. The three patients were alive without cognitive impairment at ages of 70, 69, and 65 years, showing a marked response to levodopa treatment. A 2 bp-deletion at exon 11 (1276-1277 del GA) was found. The three patients were homozygous for this frameshift mutation, which would introduce a Stop at codon 394. This is a new PARKIN-mutation that would produce a truncated protein, lacking exon 12 and most the 11th. This region includes the C-terminal ring-finger domain of parkin, essential for its function as a ubiquitin-protein ligase. Compared to patients from other families with truncating mutations, our patients had an earlier onset. In addition, the three patients had dystonia at onset. In conclusion, we described a new PARKIN truncating mutation associated with an early onset parkinsonism, and the presence of foot dystonia as the initial symptom.
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PMID:Early-onset Parkinson's disease associated with a new parkin mutation in a Spanish family. 1168 52

Mutations in the PARKIN gene have been identified in families with recessively inherited Parkinson disease (PD). Common DNA-polymorphisms at the PARKIN gene could contribute to the risk for PD in the general population. Here we searched for DNA-polymorphisms in the PARKIN promoter. We found two single nucleotide polymorphisms (-324 A/G and -797 A/G). In order to analyse the association of PD with these and two previously described polymorphisms (1281 G/A, Asp394Asn, and 601 G/A, Ser167Asn) we genotyped 105 patients and 150 healthy controls. Allele and genotype frequencies for the four polymorphisms did not differ between patients and controls, or between patients with an early-onset (< or =40 years; n = 20) and a late-onset (>40 years; n = 85). According to our data, the genetic variation at the PARKIN gene (including promoter polymorphisms) did not contribute to the risk of developing PD in the general population.
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PMID:Single-nucleotide polymorphisms in the promoter region of the PARKIN gene and Parkinson's disease. 1216 99


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