OBJECTIVE: To analyze the dynamic variant and clinical subtype of a pedigree affected with spinocerebellar ataxia (SCA) by using fluorescent-labeled primer combined with capillary electrophoresis. METHODS: Genomic DNA was extracted from 8 members including 6 patients and 2 healthy individuals from the pedigree. Six pairs of fluorescent-labeled primers were designed to screen pathological variants in association with common subtypes of SCA including SCA1, SCA2, SCA3, SCA6, SCA12 and SCA17.The PCR products were detected by capillary electrophoresis. RESULTS: The number of CAG repeats in the SCA3 gene of the proband were determined as 8 and 70, exceeded the normal range(12 to 40), which suggested a diagnosis of SCA3. The other five patients were all detected with abnormal CAG repeats in the SCA3 gene, while the two healthy individuals were determined to be within the normal range. CONCLUSION The abnormal expansion of CAG repeats in the SCA3 gene probably underlay the pathogenesis of the disease in this pedigree. Combined fluorescent-labeled primers PCR and capillary electrophoresis can detect dynamic variants among SCA patients with efficiency and accuracy.
Ataxin-3/genetics* ; Genetic Variation ; Humans ; Machado-Joseph Disease/genetics* ; Pedigree ; Repressor Proteins/genetics* ; Trinucleotide Repeats/genetics*

OBJECTIVE: Machado-Joseph disease (MJD) is a spinocerebellar ataxia, and osteoporosis is a multifactor disease that may affect patients with neurologic conditions. The frequency of osteoporosis among MJD patients, however, has not been studied. The purpose of this study is to evaluate bone mineral density (BMD) and identify correlations between clinical factors and frequency of vertebral fractures in patients with MJD. METHODS: Clinical data, lumbar X-rays and BMD data were obtained in 30 patients with MJD. RESULTS: Ten patients (33.3%) showed low BMD in at least one of the sites studied based on Z-scores. The Z-score correlated directly with body mass index, and the femoral neck Z-score was inversely correlated with cytosine-adenine-guanine (CAG) expansion. There was no correlation between BMD and other clinical factors. Forty-three percent of the patients reported previous pathologic fractures. Five patients (16.7%) had at least one fracture detected by lumbar X-ray. CONCLUSION: Low BMD and fractures are frequent among MJD patients, and careful management of BMD may be beneficial for these patients.
Body Mass Index ; Bone Density ; Femur Neck ; Fractures, Spontaneous ; Humans ; Machado-Joseph Disease ; Osteoporosis ; Spinocerebellar Ataxias

BACKGROUNDSpinocerebellar ataxia type 3 (SCA3) is the most common subtype of SCA worldwide, and runs a slowly progressive and unremitting disease course. There is currently no curable treatment available. Growing evidence has suggested that nerve growth factor (NGF) may have therapeutic effects in neurodegenerative diseases, and possibly also in SCA3. The objective of this study was to test the efficacy of NGF in SCA3 patients.

METHODSWe performed an open-label prospective study in genetically confirmed adult (>18 years old) SCA3 patients. NGF was administered by intramuscular injection (18 μg once daily) for 28 days consecutively. All the patients were evaluated at baseline and 2 and 4 weeks after treatment using the Chinese version of the scale for assessment and rating of ataxia (SARA).

RESULTSTwenty-one SCA3 patients (10 men and 11 women, mean age 39.14 ± 7.81 years, mean disease duration 4.14 ± 1.90 years, mean CAG repeats number 77.57 ± 2.27) were enrolled. After 28 days of NGF treatment, the mean total SARA score decreased significantly from a baseline of 8.48 ± 2.40 to 6.30 ± 1.87 (P < 0.001). Subsections SARA scores also showed significant improvements in stance (P = 0.003), speech (P = 0.023), finger chase (P = 0.015), fast alternating hand movements (P = 0.009), and heel-shin slide (P = 0.001).

CONCLUSIONSOur preliminary data suggest that NGF may be effective in treating patients with SCA3.

Adult ; Animals ; Female ; Humans ; Injections, Intramuscular ; Machado-Joseph Disease ; drug therapy ; Male ; Mice ; Middle Aged ; Nerve Growth Factor ; administration & dosage ; therapeutic use ; Prospective Studies

OBJECTIVETo explore the subcellular localization of ataxin-3 and the effect of polyglutamine (polyQ) expansion mutation on the morphology of mitochondrion, golgi apparatus and endoplasmic reticulum.

METHODSTransient transfection was employed to build cell models expressing wild-type or mutant ataxin-3 proteins. Indirect immunofluorescence was applied to identify markers of organelle membrane. The results were observed under a laser scanning confocal microscope.

RESULTSNo co-localization was observed for ataxin-3 protein and mitochondrial marker TOM20, but the percentage of cells with mitochondrial fragmentation has increased in cells expressing mutant ataxin-3 (P<0.05). No co-localization was observed for ataxin-3 protein and golgi marker GM130, and mutant ataxin-3 did not cause golgi fragmentation. Wide type and polyQ-expanded ataxin-3 both showed partial co-localization with ER marker calnexin. The latter showed more overlap with calnexin, and the overlapping signals were mostly located in the places where aggregates were situated.

CONCLUSIONPolyQ-expanded ataxin-3 protein may indirectly affect the integrity of mitochondria, but may cause no effect on the structure and functions of golgi apparatus. Endoplasmic reticulum may be another place where extended ataxin-3 protein can induce cytotoxicity in addition to the nucleus.

Ataxin-3 ; Cytoplasm ; genetics ; metabolism ; Endoplasmic Reticulum ; genetics ; metabolism ; HeLa Cells ; Humans ; Machado-Joseph Disease ; genetics ; metabolism ; Mitochondria ; genetics ; metabolism ; Nerve Tissue Proteins ; genetics ; metabolism ; Nuclear Proteins ; genetics ; metabolism ; Protein Transport ; Repressor Proteins ; genetics ; metabolism

BACKGROUNDSpinocerebellar ataxias (SCAs) are a group of neurodegenerative disorders that primarily cause the degeneration in the cerebellum, spinal cord, and brainstem. We study the clinical characteristics, radiological features and gene mutation in Chinese families with SCAs.

METHODSIn this study, we investigated 10 SCAs Chinese families with SCA1, SCA3/Machado-Joseph disease (MJD), SCA7, SCA8. There were 27 people who were genetically diagnosed as SCA, of which 21 people showed clinical symptoms, and 6 people had no clinical phenotype that we called them presymptomatic patients. In addition, 3 people with cerebellar ataxia and cataracts were diagnosed according to the Harding diagnostic criteria but failed to be recognized as SCAs on genetic testing. Clinical characteristic analyses of each type of SCAs and radiological examinations were performed.

RESULTSWe found that SCA3/MJD was the most common subtype in Han population in China, and the ratio of the pontine tegmentum and the posterior fossa area was negatively correlated with the number of cytosine-adenine-guanine (CAG) repeats; the disease duration was positively correlated with the International Cooperative Ataxia Rating Scale score; and the CAG repeats number of abnormal alleles was negatively correlated with the age of onset.

CONCLUSIONSCollectively our study is a systematic research on SCAs in China, which may help for the clinical diagnosis and prenatal screening of this disease, and it may also aid toward better understanding of this disease.

Adult ; DNA Repeat Expansion ; genetics ; Female ; Humans ; Machado-Joseph Disease ; genetics ; pathology ; Male ; Mutation ; genetics ; Spinocerebellar Ataxias ; genetics ; pathology ; Trinucleotide Repeat Expansion ; genetics

OBJECTIVE: To determine the value of diffusion weighted imaging (DWI) in the diagnosis of hereditary spinocerebellar ataxia 3 and the Machado Joseph disease (SCA3/MJD) and hereditary spastic paraplegia 4 (SPG4). METHODS: We scanned 13 patients with SPG4, 30 patients with SCA3/MJD (21 onset patients and 9 with only genetic abnormalities), and 27 healthy volunteers with DWI. The processing data were apparent diffusion coefficient (ADC). The above data were grouped for comparative study. RESULTS: In the precentral gyrus, posterior limb of the internal capsule, cerebral peduncle, pons, cerebellar cortex and cerebellar white matter, the ADC of onset SCA3/MJD patients increased compared with the control group. The ADC of non-onset SCA3/MJD patients increased only in the cerebellar dentate nucleus compared with the control group. In the cerebellar cortex, the ADC of onset SCA3/MJD patients was significantly higher than the non-onset SCA3/MJD. The ADC of onset SCA3/MJD patients was significantly higher in the posterior limb of the internal capsule, cerebellar cortex, cerebellar white matter and pons than that of SPG4 patients. In the precentral gyrus, the ADC of SPG4 was significantly higher than control. CONCLUSION DWI is useful in the diagnosis of SCA3/MJD and SPG4.
Diffusion Magnetic Resonance Imaging ; Humans ; Machado-Joseph Disease ; diagnosis ; Paraplegia ; diagnosis ; Spastic Paraplegia, Hereditary ; diagnosis

OBJECTIVETo investigate the clinical manifestation and the mutation characteristics of intermedial allele associated with a disease phenotype of a Machado-Joseph disease (MJD) family.

METHODSPolymerase chain reaction, capillary electrophoresis, molecular cloning and sequencing were performed to detect the ATXN3 gene in an spinocerebellar ataxia(SCA) family. The fragments of expanded alleles were subcloned into the pGEM-T plasmids and sequenced.

RESULTSThe expanded repeats at the MJD locus were confirmed by molecular technique. The proband had 43 CAG repeats at the MJD locus. He had two sons with 41 and 64 repeats in the expanded allele respectively.

CONCLUSIONA 43 CAG repeat allele was unstable upon inter-generational transmission. The change of the CAG repeat was bidirectional. This is the shortest expanded allele associated with a disease phenotype in the MJD gene reported to date. The identification of the MJD family has reduced the amplitude between the normal and expanded allele repeats.

Adult ; Alleles ; Asian Continental Ancestry Group ; ethnology ; genetics ; Ataxin-3 ; Base Sequence ; Ethnic Groups ; genetics ; Female ; Genetic Loci ; genetics ; Humans ; Machado-Joseph Disease ; genetics ; Male ; Middle Aged ; Molecular Sequence Data ; Mutation ; Nerve Tissue Proteins ; genetics ; Nuclear Proteins ; genetics ; Phenotype ; Repetitive Sequences, Nucleic Acid ; Repressor Proteins ; genetics

OBJECTIVETo investigate the role of autophagy on the pathogenesis of spinocerebellar ataxia 3/Machado-Joseph disease (SCA3/MJD).

METHODSHEK293 cells expressing polyglutamine-expanded ataxin-3 were used as cell model for SCA3/MJD. The level of polyglutamine-expanded ataxin-3 was detected after cells were treated with different inhibitors or inducer of autophagy.

RESULTSInhibition of autophagy increased aggregate formation and cell death in HEK293 cells expressing mutated ataxin-3, and vice versa.

CONCLUSIONThe data suggested that autophagy is involved in the degradation of mutant ataxin-3, resulting in a decrease in the proportions of aggregate-containing cells and cell death in HEK293 cells expressing polyglutamine-expanded ataxin-3. It is possible that autophagy may be applied as a potential therapeutic approach for SCA3/MJD.

Ataxin-3 ; Autophagy ; Cell Line ; Humans ; Machado-Joseph Disease ; genetics ; metabolism ; physiopathology ; Mutation ; Nerve Tissue Proteins ; genetics ; metabolism ; Nuclear Proteins ; genetics ; metabolism ; Peptides ; metabolism ; Repressor Proteins ; genetics ; metabolism

OBJECTIVETo establish a stable, accurate and intuitive method for detecting the CAG trinucleotide repeats of MJD1 gene.

METHODSThe CAG trinucleotide polymorphism of the MJD1 gene was analyzed by recombinant DNA technology and DNA sequencing in 35 spinocerebellar ataxia 3/Machado-Joseph disease (SCA3/MJD) patients from Mainland China.

RESULTSThe range of the CAG repeat of the 35 patients was 65-81 (mean = 72.96 +/- 4.24). The CAG repeats contained two CAAs and one AAG variations in the CAG motif in all the patients and majority of the healthy controls. There was a CGG/GGG polymorphism at the 3' end of the CAG repeat. The GGG allele was consistently associated with smaller CAG repeats in healthy controls. On the other hand, the CGG allele consistently existed in the patients.

CONCLUSIONRecombinant DNA technology can stably, accurately and intuitively detect the CAG trinucleotide repeat of the MJD1 gene. It should be used as a major technique to diagnose the SCA3/MJD and analyze the polymorphism of CAG sequence.

Adolescent ; Adult ; Ataxin-3 ; Base Sequence ; Female ; Genetic Engineering ; methods ; Humans ; Machado-Joseph Disease ; genetics ; Male ; Middle Aged ; Molecular Sequence Data ; Nerve Tissue Proteins ; genetics ; Nuclear Proteins ; genetics ; Polymorphism, Genetic ; Repressor Proteins ; genetics ; Sequence Analysis, DNA ; Trinucleotide Repeats ; Young Adult

OBJECTIVETo study the possible relationship between the mitochondrial DNA (mtDNA) mutation and spinocerebellar ataxia type 3 (SCA3).

METHODSGenetic diagnosis of SCA3 was made by detecting the CAG-repeat expansion of MJD1 gene using PCR and DNA sequencing techniques. Then polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was performed to analyze the mitochondrial DNA extracted from peripheral white blood cells from 43 patients and presymptomatic individuals diagnosed according to CAG expansion, and 30 healthy individuals. Mitochondrial DNAs of subjects with abnormal SSCP were sequenced.

RESULTSA new mitochondrial DNA deletion of 9 bp at mtDNA 8282-8290 was identified in 1 patient and 3 presymptomatic individuals.

CONCLUSIONA new deletion mutation of mitochondrial DNA in 1 SCA3 patient and 3 presymptomatic individuals is reported.

Adolescent ; Adult ; Aged ; Base Sequence ; Case-Control Studies ; Child ; Child, Preschool ; DNA Mutational Analysis ; DNA, Mitochondrial ; genetics ; Female ; Humans ; Machado-Joseph Disease ; genetics ; Male ; Middle Aged ; Molecular Sequence Data ; Mutation ; Polymerase Chain Reaction ; Polymorphism, Single-Stranded Conformational ; Sequence Deletion