Charcot-Marie-Tooth disease (CMT) is the most common form of hereditary neuropathy with significant clinical and genetic heterogeneity. So far 28 genes have been cloned. The main clinical manifestations of CMT include progressive distal muscle wasting and weakness, impaired distal sensation, and diminishing or loss of tendon reflex. Patients may be classified into demyelinating type (CMT1) and axonal type (CMT2) according to electrophysiological and pathological characteristics. Establishment of a standard diagnostic procedure based on clinical, electrophysiological and pathological findings will enable accurate diagnosis in most CMT patients and provide guidance for gene consulting and prognosis.
Charcot-Marie-Tooth Disease ; classification ; diagnosis ; genetics ; Humans

OBJECTIVETo study the relationship between single nucleotide polymorphisms of paraoxonase 2 (PON2) and stroke.

METHODSObjects examined comprised of three groups: 120 healthy people, 150 patients with cerebral hemorrhage, 180 patients with cerebral infarction. The PON2 genotypes were determined with PCR and digested by specific restriction enzymes.

RESULTSC311S and G148A polymorphisms of PON2 gene existed among population of Chinese Hunan area, with the allele frequencies 0.23/0.77 for C/S and 0.57/0.43 for G/A in the control group. There was no significant difference of genotype and allele frequency between stroke patients and controls (P>0.05).

CONCLUSIONC311S polymorphism of PON2 has no significant correlation with stroke in Han people of Chinese Hunan area and allele C/S is not an independent risk factor for stroke,neither is G148A.

Aged ; Aryldialkylphosphatase ; genetics ; Asian Continental Ancestry Group ; genetics ; Case-Control Studies ; Female ; Humans ; Male ; Middle Aged ; Polymerase Chain Reaction ; Polymorphism, Single Nucleotide ; Stroke ; genetics

OBJECTIVETo study the effect of Charcot-Marie-Tooth 2L disease causing gene K141N mutation in heat shock protein B8 gene (HSPB8) on cell viability.

METHODSBy using liposome transfection technique, (wt)HSPB8, (K141N)HSPB8 eukaryotic expression vector and green fluorescent protein (GFP) vector were transfected into SHSY-5Y cell, respectively. Twenty-four hours later, the cells were treated with 44 degree centigrade lethal heat shock for 40 minutes. The relative viability of SHSY-5Y cells in each group was tested by using tetrazole blue colorimetric method (methyl thiazolyl tetrazolium, MTT).

RESULTSThere were significant differences among the light absorption value of GFP, pEGFP-(wt)HSPB8 and pEGFP-(K141N)HSPB8 transfected groups after heat shock (P<0.05), indicating that the relative viability of cells overexpressed with (wt)HSPB8 and (K141N)HSPB8 was different from that of control cells. The viability of cells overexpressing (wt)HSPB8 was highest, followed by cells overexpressed with (K141N)HSPB8. The viability of cells tranfected with GFP only was the lowest.

CONCLUSIONHSPB8 may play an important role in the protection of cells under lethal heat shock treatment, and the K141N mutation can impair the protective effect.

Cell Line, Tumor ; Cell Survival ; genetics ; Charcot-Marie-Tooth Disease ; genetics ; metabolism ; Gene Expression Regulation ; Genetic Vectors ; genetics ; Heat-Shock Proteins ; genetics ; metabolism ; Humans ; Mutation ; genetics ; Protein-Serine-Threonine Kinases ; genetics ; metabolism

Brain magnetic resonance imaging (MRI) of the elderly often reveals white matter changes (WMCs) with substantial variability across individuals.Our study was designed to explore MRI features and site-specific factors of ischemic WMCs.Clinical data of consecutive patients diagnosed with ischemic cerebral vascular disease who had undergone brain MRI were collected and analyzed.Multi-logistic regression analysis comparing patients with mild versus severe WMCs was performed to detect independent associations.Analyses of variance (ANOVAs) were used to detect regionally specific differences in lesions.We found that lesion distribution differed significantly across five cerebral areas,with lesions being predominant in the frontal lobe and parieto-occipital area.To explore WMCs risk factors,after adjusting for gender,diabetes mellitus,and hypertension,only age (P＜0.01),creatinine (P=0.01),alkaline phosphatase (ALP) (P=0.01) and low-density lipoprotein cholesterol (LDL-C) (P=0.03) were found to be independently associated with severe WMCs.Age (P＜0.001) was strongly associated with WMCs in the frontal lobe while hypertension was independently related to lesions in the basal ganglia (P=0.048) or infratentorial area (P=0.016).In conclusion,MRI of WMCs showed that ischemic WMCs occurred mostly in the frontal lobe and parieto-occipital area.The infratentorial area was least affected by WMCs.Typically,age-related WMCs were observed in the frontal lobes,while hypertension-related WMCs tended to occur in the basal ganglia and infratentorial area.

Objective To study the PINK1 aggresome formation and it's features in response to proteasomal inhibition.Methods Full-length PINK1 cDNA were amplified by polymerase chain reaction (PCR)from fetus brain cDNA library and subcloned into the EcoR I and BamH I sites of the vector pEGFP- N1.The integrity of the constructs was confirmed by sequencing.COS-7 cells were transiently transfected with PINK1-pEGFP-N1 using Lipofectamine 2000.Cells were treated by MG-132 in order to test the effect of proteasome inhibition on aggregation formation.The protein level of wild-type PINK1 with or without MG-132 treatment was confirmed by Western blot analysis.The formation of PINK1 aggregates was tested by fluorescence and the presence of ubiquitin,and ?-synuclein in PINK1 aggregates was examined by immunofluorescence and confocal microscopy.Results The expression level of PINK1 was significant increased into the form of aggregate in cells treated with MG-132;immunostaining for endogenous ubiquitin and ?-synuclein revealed a co-localization of both proteins in PINK1-positive aggregates.Conclusions In the presence of MG-132,overexpressed PINK1 forms into aggregates,whose components are ubiquitin and ?-synuclein.

OBJECTIVETo clone the disease-causing genes possibly existing in 6.8 cM distance between microsatellite markers D12S1720 and D12S1611 in chromosome 12q24 for Charcot-Marie-Tooth disease type 2L (CMT2L).

METHODSTen positional and functional candidate genes were chosen among all known genes in this locus region by bioinformatics inqury. Mutation detection was performed by sequencing the exons and intron-exon junctions of the candidate genes.

RESULTSEleven sequence variations, that included 5 heterozygous and 6 homozygous variations, were detected in the exons and flanking areas of the 10 candidate genes. All the variations showed no co-segregation with disease phenotype.

CONCLUSIONTen candidate genes(TAOK3, RAB35, RPLP0, PXN, RNF10, RHOF, VPS33A, RSN, DENR, RNP24) were ruled out as the disease-causing gene for CMT2L. Ten single nucleotide polymorphisms (SNP) were reported for the first time.

Base Sequence ; Charcot-Marie-Tooth Disease ; genetics ; Chromosomes, Human, Pair 12 ; genetics ; Cloning, Organism ; DNA ; analysis ; DNA Mutational Analysis ; Humans ; Molecular Sequence Data ; Nucleic Acid Amplification Techniques

OBJECTIVETo investigate over-expression of wild-type alpha-synuclein inducing the aberrant aggregation of alpha-synuclein in HEK293 cell in vitro.

METHODSThe cDNA encoding the human alpha-synuclein without the stop code was cloned into PGEM T-easy vector. Using enzyme map and DNA sequencing analyzed and determined the recombinant plasmid, and then sub-clone the alpha-synuclein cDNA fragment into pEGFP-N1 vector. The recombinant plasmids alpha-synuclein-pEGFP were transfected into HEK293 cells by lipofectamin 2000. The aberrant aggregation of alpha-synuclein was measured by EGFP fluorescence, anti-alpha-synuclein immunocytochemistry. The inclusions in the cultured cells were identified with HE staining.

RESULTSThe restriction enzyme map suggested that eukaryotic expression vector for human wild-type alpha-synuclein gene was constructed successfully. By EGFP fluorescence, anti-alpha-synuclein immunocytochemistry, it could be observed that the alpha-synuclein protein could aggregate in cytoplasm and the Lewy body-like inclusions found in cytoplasm of cultured cells.

CONCLUSIONThe over-expression of wild-type alpha-synuclein can induce protein aberrant aggregation and Lewy body-like inclusions formation in cytoplasm of HEK293 cell in vitro.

Cells, Cultured ; Gene Expression ; Humans ; Immunohistochemistry ; Inclusion Bodies ; metabolism ; Lewy Bodies ; metabolism ; Parkinson Disease ; genetics ; metabolism ; alpha-Synuclein ; genetics ; metabolism

OBJECTIVETo study the mutation feature of ganglioside-induced differentiation associated protein-1 (GDAP1) gene in Chinese Charcot-Marie-Tooth disease(CMT) patients.

METHODSMutation analysis was carried out by use of polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP) combined with DNA direct sequencing of the six exons and their flanking regions of GDAP1 gene in twenty-three CMT patients, including 8 probands of autosomal recessive CMT families and 15 sporadic patients.

RESULTSA compound heterozygous mutation A533G and A767G were unveiled in one autosomal recessive CMT kindred. The homozygous and heterozygous T507G were common SNPs in Chinese population.

CONCLUSIONA533G and A767G of GDAP1 gene were new mutations firstly reported.

Adolescent ; Adult ; Charcot-Marie-Tooth Disease ; genetics ; Child ; Child, Preschool ; Female ; Humans ; Male ; Mutation ; Nerve Tissue Proteins ; genetics ; Polymerase Chain Reaction ; Polymorphism, Single-Stranded Conformational ; Sequence Analysis, DNA

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

BACKGROUNDDominantly inherited spinocerebellar ataxia (SCA) is a clinically and genetically heterogeneous group of neurodegenerative disorders. This study was to further assess the frequency of SCA1 (spinocerebellar ataxia type 1), SCA2, SCA3/MJD (spinocerebellar ataxia type 3/Machado-Joseph disease), SCA6, SCA7, SCA8, SCA10, SCA12, SCA14, SCA17 and DRPLA (dentatorubro-pallidoluysian atrophy) in mainland Chinese, and to specifically characterize mainland Chinese patients with SCA6 in terms of clinical and molecular features.

METHODSUsing a molecular approach, we investigated SCA in 120 mainland Chinese families with dominantly inherited ataxias and in 60 mainland Chinese patients with sporadic ataxias. Clinical and molecular features of SCA6 were further characterized in 13 patients from 4 families.

RESULTSSCA3/MJD was the most common type of autosomal dominant SCA in mainland Chinese, accounting for 83 patients from 59 families (49.2%), followed by SCA2 [8 (6.7%)], SCA1 [7 (5.8%)], SCA6 [4 (3.3%)], SCA7 [1 (0.8%)], SCA8 (0%), SCA10 (0%), SCA12 (0%), SCA14 (0%), SCA17 (0%) and DRPLA (0%). The genes responsible for 41 (34.2%) of dominantly inherited SCA families remain to be determined. Among the 60 patients with sporadic ataxias in the present series, 3 (5.0%) was found to harbor SCA3 mutations while none was found to harbor SCA6 mutations. In the 4 families with SCA6, significant anticipation was found in the absence of genetic instability on transmission.

CONCLUSIONA geographic cluster of families with SCA6 subtype was initially identified in a mainland Chinese population.

Adult ; Asian Continental Ancestry Group ; Calcium Channels ; genetics ; Female ; Gene Frequency ; Genes, Dominant ; Humans ; Male ; Middle Aged ; Spinocerebellar Ataxias ; genetics ; Trinucleotide Repeats