The genetics of the dystonias – a review based on the new classification of the dystonias / A genética das distonias – uma revisão baseada na nova classificação das distonias

The definition and classification of the dystonias was recently revisited. In the new 2013 classification, the dystonias are subdivided in terms of their etiology according to whether they are the result of pathological changes or structural damage, have acquired causes or are inherited. As hereditary dystonias are clinically and genetically heterogeneous, we sought to classify them according to the new recently defined criteria. We observed that although the new classification is still the subject of much debate and controversy, it is easy to use in a logical and objective manner with the inherited dystonias. With the discovery of new genes, however, it remains to be seen whether the new classification will continue to be effective.

O conceito e a classificação das distonias foram recentemente revisados. Na nova classificação de 2013, quanto à etiologia, as distonias podem ser subdividas em relação às alterações patológicas, aos danos estruturais, às causas adquiridas e à hereditariedade. Como as distonias hereditárias são clínica e geneticamente heterogêneas, buscamos classifica-las segundo os novos critérios estabelecidos recentemente. Observamos que apesar da nova classificação das distonias ainda ser objeto de discussões e controvérsias, ela pode usada com facilidade, de uma maneira lógica e objetiva, no contexto das distonias hereditárias. Com a descoberta de novos genes poderemos observar se essa classificação continuará sendo efetiva.

Non-choreic movement disorders as initial manifestations of Huntington's disease

We describe seven patients with genetically confirmed Huntington's disease (HD) who had non-choreic movement disorders as presenting symptoms or signs. Patients with movement disorders other than chorea in the early stages tended to have larger CAG trinucleotide repeat expansion in comparison with more "typical" HD patients.

Nós descrevemos sete pacientes com doença de Huntington, geneticamente confirmada, cuja apresentação motora inicial foi diferente de coréia. Pacientes com manifestação motora inicial diferente de coréia apresentaram maior número de expansões repetidas de CAG trinucleotídeo quando comparados com aqueles com sintomatologia motora "típica".

Tau and tauopathies.

Tau protein is a neuronal microtubule-associated protein (MAP), which localizes primarily in the axon. It is one of the major and most widely distributed MAPs in the central nervous system. Its biochemistry and molecular pathology is being increasingly studied. Tau is a key component of neurofbrillary tangles in Alzheimer's disease (AD). Disorders with neuronal, oligodendroglial or astrocytic filamentous tau inclusions are now grouped under the common rubric of tauopathies. The discovery of mutations in the tau gene, located on Chromosome 17 and its relationship to frontotemporal dementia with Parkinsonism (FTDP-17) has enhanced the importance of tau protein in cognitive neurology. Aberrant aggregates of tau have been documented in most of the neurodegenerative diseases with filamentous inclusions. The role of cerebrospinal fluid tau in the diagnosis of dementias is being investigated quite extensively. Recently, it has been shown that Abeta immunotherapy leads to the clearance of early tau pathology. It is becoming clearer that understanding tau better will lead to better understanding of many neurodegenerative diseases that may help develop interventional strategies.

Estudo genético da doença de Parkinson / Genetical study of Parkinson's disease

A doença de Parkinson (DP) é a segunda doença neurodegenerativa mais comum com uma prevalência aproximada de 3 por cento em pacientes com mais de 65 anos. É doença esporádica, mas o parkinsonismo primário (PP) familiar, decorrente de defeitos genéticos específicos, tem sido encontrado em cerca de 10 por cento dos casos diagnosticados como DP. Este estudo teve por fim o rastreamento de mutações em genes relacionados ao parkinsonismo em pacientes com PP de início precoce (< 40a) ou com história familiar positiva. Investigamos 53 probandos do Grupo de Estudo de Distúrbios do Movimento da Clínica Neurológica do HCFMUSP. Foram encontradas 4 famílias portadoras de mutações no gene PARK2, duas no PARK8 e uma no PARK9...

Parkinson disease (PD) is the second most common neurodegenerative disorder affecting approximately 3 per cent of the population over age 65. Most cases of PD manifest in sporadic form, but familial primary parkinsonism (PP) due genetical abnormalities has been found in about 10 per cent of cases diagnosed as PD. The aim of this study was to analyze the DNA of PP patients seen at the Group for the Study of Movement Disorders of the Neurology Department of HCFMUSP who presented early onset of the disease (< 40 years of age) or positive family history, with the purpose of screening candidate mutations for the disease. We found four families carrying mutations in gene PARK2, two in PARK8, and one in PARK9...

Homozygous Exon 4 Deletion in Parkin Gene in a Korean Family with Autosomal Recessive Early Onset Parkinsonism

The gene responsible for autosomal recessive parkinsonism, parkin, has recently been identified on chromosome 6q. It has been shown to be mutated in Japanese and European families, most of whom had early-onset parkinsonism. Here, we present a family with young-onset parkinsonism of an autosomal recessive inheritance. A homozygous exon 4 deletion in the parkin gene was found in 3 family members. To the best of the authors' knowledge, this is the first report in Korea of familial parkinsonism with the parkin gene mutation.

Prion disease resembling frontotemporal dementia and parkinsonism linked to chromosome 17

OBJECTIVE: To compare the clinical features of a familial prion disease with those of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). BACKGROUND: Prion diseases are not usually considered in the differential diagnosis of FTDP-17, since familial Creutzfeldt-Jakob disease (CJD), the most common inherited prion disease, often manifests as a rapidly progressive dementia. Conversely, FTDP-17 usually has an insidious onset in the fifth decade, with abnormal behavior and parkinsonian features. METHOD: We present the clinical features of 12 patients from a family with CJD associated with a point mutation at codon 183 of the prion protein gene. RESULTS: The mean age at onset was 44.0 Ý 3.7; the duration of the symptoms until death ranged from two to nine years. Behavioral disturbances were the predominant presenting symptoms. Nine patients were first seen by psychiatrists. Eight patients manifested parkinsonian signs. CONCLUSION: These clinical features bear a considerable resemblance to those described in FTDP-17