MiR-200a with CDC7 as a direct target declines cell viability and promotes cell apoptosis in Wilm's tumor via Wnt/ß-catenin signaling pathway.

MiR-200a acts as a key role in tumor malignant progression. This work purposed to assess the function of miR-200a in Wilm's tumor. Based on bioinformatics analysis, the expression, prognostic value and related pathways of miR-200a and CDC7 (a potential downstream molecule of miR-200a) in Wilm's tumor were analyzed. qRT-PCR was conducted to confirm the miR-200a level in Wilm's tumor cells. The luciferase reporter assay was carried out to verify the binding of miR-200a to 3'-UTR of CDC7. Then, the impacts of miR-200a and CDC7 on cell viability and apoptosis were measured using CCK-8 and flow cytometry assays. Also, western blot was applied to measure the expression of CDC7 as well as Wnt/ß-catenin signaling pathway-related proteins and apoptosis proteins. Herein, we revealed that miR-200a was lowly expressed in Wilm's tumor tissues and cells and the low miR-200a expression is closely bound up with death and poor outcomes. Moreover, miR-200a directly targeted and inhibited CDC7 in Wilm's tumor cells. Biological function experiments illustrated that overexpression of miR-200a reduced the viability and elevated the apoptosis of Wilm's tumor cells, while overexpression of CDC7 reversed the inhibitory impact of miR-200a on cell viability and the promoting impact of miR-200a on cell apoptosis. Besides, we revealed that miR-200a/CDC7 axis can decrease the expression of ß-Catenin, Cyclin D1 and C-Myc as well as the phosphorylation of GSK-3ß, thus inhibiting the Wnt/ß-catenin signaling pathway. Furthermore, blocking the Wnt/ß-catenin signaling pathway caused an increase on cell apoptosis, while overexpression of CDC7 can reverse these impacts. Collectively, miR-200a/CDC7 axis involved in regulating the malignant phenotype of Wilm's tumor through Wnt/ß-catenin signaling pathway, which provides a theoretical basis for targeted molecular therapy of Wilm's tumor.

Observation on the changes of clinical symptoms, blood and brain copper deposition in Wilson disease patients treated with dimercaptosuccinic acid for 2 years.

OBJECTIVE: To compare the clinical symptoms, brain copper deposition changes of Meso-2,3-dimercaptosuccinic acid (DMSA) and penicillamine therapy in patients with Wilson disease (WD) within 2 years. METHODS: 68 drug-naive patients with WD were enrolled. 10 WD patients treated with zinc gluconate alone were used as the control group. Neurological symptoms were scored using the modified Young Scale. Liver function tests, copper indices and sensitive weighted imaging (SWI) examination were collected. The values of corrected phase (CP) were collected. WD patients were treated with DPA (group 1) or DMSA (group 2) for two years, and followed up every 2 months. RESULTS: The ratio of neurological improvement in group 2 was higher than that in group 1 (P = 0.029). Higher rate of neurologic worsening was noticed in patients treated with DPA vs DMSA (P = 0.039). The post-treatment neurological score of DMSA group was lower than that of Zn group (P = 0.037). Hepatic function in 63.3% of patients was stable, while 16.7% was improved, and 20% was deteriorated, after DMSA therapy. Urinary copper levels were lower 1 month (p = 0.032), 4 months (p = 0.041), 12 months (p = 0.037) after initiation of treatment in group 2 than in group 1. At the first year of treatment, the CP values in globus pallidus and substantia nigra in group 2 were higher than those in group 1 (P = 0.034,0.039). At the second year of treatment, the CP values of substantia nigra in group 2 were higher (P = 0.041). Discontinuation was more common in patients on DPA therapy (P = 0 0.032). CONCLUSIONS: DMSA could remove metal from brain tissue faster than DPA. DMSA is effective for neurologic symptoms, while the outcome for hepatic symptoms is not entirely satisfactory. DMSA therapy is better tolerated than DPA.

A study of susceptibility-weighted imaging in patients with Wilson disease during the treatment of metal chelator.

OBJECTIVE: A randomized-controlled trial comparing study of the changes in brain sensitive-weighted imaging (SWI) of Wilson disease (WD) patients during the treatment with metal chelator was done. METHODS: 100 untreated WD patients (80 cases of cerebral type, 20 cases of hepatic type, age 20.13 ± 9.12 years old) and 20 normal controls were selected. Neurological symptoms were scored using the modified Young scale. Liver function tests and copper indices were collected. All study objects received SWI test of the brain. The values of corrected phase (CP) were calculated on SWI. Cerebral-type WD patients were treated with D-penicillamine (DPA) (group 1) or Dimercaptopropane Sulfonate (DMPS) + Dimercaptosuccinic Acid (DMSA) (group 2). Hepatic-type WD patients were treated with DPA (group 3). All patients received annual neurological symptom score, liver function, copper indices, and SWI examination. RESULTS: At the first year of treatment, score of the modified Young scale in group 2 was lower than that in group 1 (P = 0.023) and lower than that before treatment (P = 0.040). After 2 years of treatment, the score of the modified Young scale in group 1 was lower than that before treatment (P = 0.012). At the second year after treatment, the urinary copper in group 2 was higher than that in group 1 (P = 0.014). Urinary copper was maintained at 200 µg/day in group 1 and 300 µg/day in group 2 after 3 years of treatment. At the first year of treatment, serum copper in group 1 was lower than that in group 2 (P = 0.032). At the first year of treatment, CP values of the pallidum and substantia nigra in group 2 were higher than those in group 1 (P = 0.026, 0.040). At the second year of treatment, CP value of substantia nigra in group 2 was higher than that in group 1 (P = 0.037). After 3 years of treatment, there was no difference in CP values between WD patients and normal controls. CONCLUSIONS: Therapy with DMPS and DMSA improves neurological symptoms of WD patients more quickly and leads to less aggravation, compared with therapy with DPA. The metal content in the brain of WD patients was at a low level after 3 years of treatment. DMPS and DMSA can remove metal from brain tissue faster than DPA.

Injury factors and pathological features of toxic milk mice during different disease stages.

OBJECTIVE: To evaluate different injury factors and pathological characteristics of the brain at different disease stages in toxic milk (TX) mice, an animal model of Wilson's disease (WD). METHODS: Thirty TX mice (10 each at 3, 6 and 12 months old) and 30 age-matched C57 mice were used in this study. Corrected phase (CP) values were determined from susceptibility-weighted images. Myelin content was determined by measuring inhibition optical density values of Luxol fast blue-stained sections. Neurofilament protein 68 kDa (NF68), ß-amyloid precursor protein (ß-APP), and myelin basic protein (MBP) levels, as well as copper and iron content, in brain nuclei of the TX mouse were evaluated. Gene amplification ratios for catalase (CAT), GSH peroxidase (GSH-PX), nitric oxide synthase (NOS), and superoxide dismutase (SOD) in mouse brain were also determined. RESULTS: Compared with C57 mice, neuronal cell counts were decreased in 12-months-old TX mice (p = .011). Myelin content was decreased in the lenticular nucleus (p = .029), thalamus (p = .030), and brainstem (p = .034) of 6-months-old TX mice; decreases in the corresponding nuclei (p = .044, .037, and .032, respectively) were also found in 12-months-old TX mice. MBP values were lower in the lenticular nucleus and thalamus (p = .027 and .016, respectively) of 6-months-old TX mice and in the corresponding nuclei (p = .24 and .040) of 12-months-old TX mice. NF-68 values were lower in the lenticular nucleus and thalamus (p = .034 and .037, respectively) of 6-months-old TX mice and in the corresponding nuclei (p = .006 and .012) of 12-months-old TX mice. ß-APP values were higher in the thalamus of 6-months-old (p = .037) and 12-months-old (p = .012) TX mice. Iron content was higher in the lenticular nucleus, thalamus, and cerebellum (p = .044, .038, and .029, respectively) of 6-months-old TX mice and in the corresponding nuclei (p = .017, .024, and .029) of 12-months-old TX mice. The NOS gene amplification multiple was higher (p = .039), whereas the SOD1 gene amplification multiple was lower (p = .041) in 12-months-old TX mice. There was no correlation between metal content or oxidation index and pathological index. CONCLUSIONS: The pathological characteristics of the brains of TX mice may differ at different ages. Different pathogenic factors, including copper and iron deposition and abnormal oxidative stress, are present at different stages.

The asymmetry of neural symptoms in Wilson's disease patients detecting by diffusion tensor imaging, resting-state functional MRI, and susceptibility-weighted imaging.

Objective: To investigate the cause of the motor asymmetry in Wilson's disease (WD) patients using functional MRI. Methods: Fifty patients with WD and 20 age-matched healthy controls were enrolled. Neurological symptoms were scored using the modified Young Scale. All study subjects underwent diffusion tensor imaging (DTI), susceptibility-weighted imaging (SWI), and resting-state functional MRI (rs-fMRI) of the brain. Six regions of interest (ROI) were chosen. Fiber volumes between ROIs on DTI, corrected phase (CP) values on SWI, amplitude of low-frequency fluctuation (ALFF), and regional homogeneity (REHO) values on rs-fMRI were determined. Asymmetry index (right or left value/left or right value) was evaluated. Results: Asymmetry of rigidity, tremor, choreic movement, and gait abnormality (asymmetry index = 1.33, 1.39, 1.36, 1.40), fiber tracts between the GP and substantia nigra (SN), GP and PU, SN and thalamus (TH), SN and cerebellum, head of the caudate nucleus (CA) and SN, PU and CA, CA and TH, TH and cerebellum (asymmetry index = 1.233, 1.260, 1.269, 1.437, 1.503, 1.138, 1.145, 1.279), CP values in the TH, SN (asymmetry index = 1.327, 1.166), ALFF values, and REHO values of the TH (asymmetry index = 1.192, 1.233) were found. Positive correlation between asymmetry index of rigidity and fiber volumes between the GP and SN, SN and TH (r = .221, .133, p = .043, .036), and tremor and fiber volumes between the CA and TH (r = .045, p = .040) was found. Conclusions: The neurological symptoms of patients with WD were asymmetry. The asymmetry of fiber projections may be the main cause of motor asymmetry in patients with WD.

Oculomotor deficits in spinocerebellar ataxia type 3: Potential biomarkers of preclinical detection and disease progression.

AIMS: To detect specific oculomotor deficits in preclinical stage of spinocerebellar ataxia type 3 (SCA3) and evaluate whether these abnormalities prove useful as potential biomarkers of disease progression. METHODS: A Chinese cohort of 56 patients with SCA3, including 12 preclinical carriers of SCA3 (pre-SCA3) and 44 manifest SCA3, and 26 healthy control individuals were recruited. We performed a detailed investigation on central oculomotor performance including fixation, gaze, smooth pursuit, prosaccade, and antisaccade using video-oculography. RESULTS: Common oculomotor features of pre-SCA3 included square-wave jerk during central fixation and gaze holding, impaired vertical smooth pursuit, slow upward saccade, and increased antisaccade error rate. In our SCA3 cohort, all oculomotor parameters were correlated with the score of the Scale for the Assessment and Rating of Ataxia, whilst some of them were correlated with disease duration. CONCLUSION: This study showed that a series of neuropathological changes reflected by oculomotor abnormalities appeared preferentially in preclinical stage of SCA3. Accordingly, objective oculomotor preclinical signs may be useful to detect the optimum time-point for therapeutic interventions in future clinical trials of SCA3. Larger and longitudinal data are warranted to confirm our results.

Diffusion tensor imaging of the extracorticospinal network in the brains of patients with Wilson disease.

OBJECTIVE: To evaluate damage to the extracorticospinal tract in Wilson disease (WD) patients using diffusion tensor imaging (DTI). METHODS: 70 patients with WD, including 50 with cerebral type and 20 with hepatic type, and 20 age-matched healthy controls were enrolled. Neurological symptoms were scored using the modified Young Scale. Patients with cerebral type WD were divided into four subgroups: those with (1) hypokinesia, (2) parkinsonism, (3) mouth and throat dystonia, and (4) psychiatric symptoms. All study subjects underwent DTI of the brain. Five regions of interest (ROIs) were chosen. Fractional anisotropy (FA) and fiber volumes between ROIs were determined, and the relationships between DTI metrics and clinical status were evaluated. RESULTS: FA values and fiber volumes between subcortical nuclei were lower in WD patients. Fiber volumes between the putamen (PU) and the globus pallidus (GP), substantia nigra (SN), and thalamus (TH); between the head of the caudate nucleus (CA) and the GP and TH; and between the TH and cerebellum were lower in group 1 than in the other groups of WD patients. Fiber volumes between the GP and the SN and TH were lower in group 2, and fiber volumes between the SN and TH were lower in group 3. DTI metrics differed between patients with the cerebral and hepatic types of WD. CONCLUSIONS: DTI can reconstruct the network of the extracorticospinal tract. Fiber projection between subcortical nuclei was abnormal in WD patients. Damage to fiber connections may correlate with neurological symptoms in WD patients.

Characterizing brain mineral deposition in patients with Wilson disease using susceptibility-weighted imaging.

AIMS: The aim of this study was to evaluate the feasibility of characterizing the brain-mineral deposition in patients with Wilson disease (WD) using susceptibility-weighted imaging (SWI). MATERIALS AND METHODS: The study enrolled 30 WD patients and 20 age-matched healthy controls. Neurological symptoms were scored using the modified Young Scale. The hepatic function indices, serum and urinary copper content, and serum iron content were determined. All study objects received the magnetic resonance imaging (MRI) and SWI test of the brain. The values of corrected phase (CP) were calculated on SWI. The relationship between CP values and the clinical status were evaluated. RESULTS: The serum iron content of WD patients was higher than the normal. The CP values of substantia nigra, caudate nucleus, and globus pallidus of WD were lower than the normal values, while the CP value of substantia nigra was the lowest. No correlations were determined between the CP values and the iron and copper parameters. There was negative correlation between the scores of dysarthria and the CP values of the globus pallidus. There was negative correlation between the scores of tremor and the CP values of caudate nucleus. Some regions, which had high signals on T2-weighted image, had low signals on SWI. CONCLUSIONS: There might be abnormal iron metabolism in patients with WD. The decreased CP values might reflect a deposition of both copper and iron. SWI may be more sensitive than the ordinary MRI. The mineral deposition may contribute to the neural symptoms.

Cognitive impairment in native Chinese with spinocerebellar ataxia type 3.

BACKGROUND: Previous studies have shown cognitive impairment in patients with spinocerebellar ataxia type 3 (SCA3). However, there is a lack of data on Chinese patients with SCA3. METHOD: We investigated 22 native Chinese with SCA3 and 18 controls matched for age, education as well as mental status. Cognitive assessments were carefully carried out to measure verbal fluency, memory, attention, executive function, visuospatial and visuoconstructive functions. RESULTS: The most common impairments of cognition in native Chinese with SCA3 were disruption of phonemic verbal fluency and frontal executive dysfunction. Deficits in semantic fluency were detected in about 31.8% patients. Impaired visuospatial function and verbal memory were also found in native Chinese with SCA3. The degree of ataxia, CAG repeat length and education were found to correlate with cognitive performance. Multivariate binary logistic regression suggested that an oculomotor disorder and depression are predictors of cognitive impairment. CONCLUSION: Native Chinese with SCA3 had cognitive impairment of frontal executive function, temporal and parietal functions. An oculomotor disorder might be an index of cognitive dysfunction.

Penicillamine increases free copper and enhances oxidative stress in the brain of toxic milk mice.

Wilson disease (WD) is characterized by the accumulation of copper arising from a mutation in the ATP7B gene. Penicillamine (PA) makes 10-50% of the patients with neurologic symptoms neurologically worse at the early stage of administration. The aim of this study was to determine how the copper metabolism changes and whether the change impairs the brain of toxic milk (tx) mice, an animal model of WD, during the PA administration. The free copper and protein-bound copper concentrations in the serum, cortex and basal ganglia of tx mice with PA administration for 3 days, 10 days and 14 days, respectively, were investigated. The expression of copper transporters, ATP7A and CTR1,was analyzed by real-time quantitative PCR, immunofluorescence and Western blot. Then SOD, MDA and GSH/GSSG were detected to determine whether the oxidative stress changed correspondingly. The results revealed the elevated free copper concentrations in the serum and brain, and declined protein-bound copper concentrations in the brain of tx mice during PA administration. Meanwhile, transiently increased expression of ATP7A and CTR1 was observed generally in the brain parenchyma by immunofluorescence, real-time quantitative PCR and Western blot. Additionally, ATP7A and CTR1 were observed to locate mainly at Golgi apparatus and cellular membrane respectively. Intense staining of ATP7A in the choroid plexus was found in tx mice on the 3rd and 10th day of PA treatment, but rare staining of ATP7A and CTR1 in the blood-brain barrier (BBB). Decreased GSH/GSSG and increased MDA concentrations were also viewed in the cortex and basal ganglia. Our results suggested the elevated free copper concentrations in the brain might lead to the enhanced oxidative stress during PA administration. The increased free copper in the brain might come from the copper mobilized from brain parenchyma cells but not from the serum according to the ATP7A and CTR1 expression analysis.

[Values of serum copper and serum free copper in the diagnosis and monitoring of Wilson's disease and its carriers].

OBJECTIVE: To explore the values of serum copper and serum free copper in the diagnosis of Wilson's disease (WD), its carrier and viral hepatitis and explore the guiding significance of monitoring serum copper in the treatment of WD. METHODS: A total of 80 WD patients (hepatic type, n = 60; encephalic type, n = 20), 30 carriers, 20 patients with viral hepatitis were enrolled and their levels of serum copper were determined. The neural symptoms were scored by modified Young grade. Hemogram, hepatic functions, blood clotting functions, serum copper and urinary copper were tested throughout all 8 courses of treatment with sodium dimercaptopropane sulfonate (DMPS). The patients were treated with zinc after discharging. All data were analyzed. RESULTS: The free serum copper increased in the patients with WD (0.17 mg/L ± 0.04 mg/L), carriers (0.13 mg/L ± 0.03 mg/L) and severe viral hepatitis (0.12 mg/L). A slight increase was also observed in the WD carriers. The level of serum copper was correlated with hepatic functions but not with the severity of neural symptoms. The serum copper increased in the patients with no improvement of neural symptoms. However, the serum copper decreased in the WD patients with the improvement of neural symptoms. The serum copper was stabilized at approximately 0.2 mg/L during the long-term treatment period. CONCLUSION: There is auxiliary diagnosis significance of serum copper in the determination of WD. Hepatic functions in hepatic type WD affect the level of serum copper. The serum copper of encephalic type WD can not indicate the severity of neural symptoms. The elevated level of serum copper indicates a poor prognosis. The serum copper is an effective marker in monitoring the development and therapeutic efficacy of the disease.

[Study of copper metabolism and liver damage in TX Mice-an animal model for liver disease].

OBJECTIVE: To provide right time points in selection of right aged animals and the normal physiological data of TX mice. METHODS: 7-12 months old TX and DL mice were studied, each group contained 3 female and 3 male mice of TX or DL mice. The concentration of copper in the serum, dry tissues (liver, brain and kidney), together with copper biochemistry indexes were measured. The liver histopathology was observed under light microscopy and electron microscope. RESULTS: Transaminase increased significantly only in 10 and 11-month- old (AST(TX10) = 218.3 U/L, AST(TX11) = 197.5 U/L, AST(DL10) = 171.5 U/L, AST(DL11) = 165.0 U/L, P(10) less than 0.001, P(11) = 0.022), but the copper concentration of liver, brain and kidney was significantly increased during 7-12 month old (the average concentration of copper, Liver(TX) = (750.0 +/- 85.5) mg/kg, Brain(TX) = (39.7 +/- 2.2)mg/kg, Kidney(TX) = (29.8 +/- 5.0) mg/kg, Liver(DL) = (11.6 +/- 1.5) mg/kg, Brain(DL) = (16.8 +/- 0.9) mg/kg, Kidney(DL) = (14.2 +/- 1.0) mg/kg, t = 21.16, 23.60, 7.47, for all these organs P less than 0.05). CONCLUSION: TX mice is a suitable model of liver disease with natural recovery, so selecting animal model of suitable time point is very important.

[Clinical manifestations and molecular genetics of spinal bulbar muscular atrophy: report of 5 cases].

OBJECTIVE: To study the clinical and molecular genetic characteristics of spinal bulbar muscular atrophy (SBMA). METHODS: The clinical data, including case history, physical examination, biochemical analyses of blood, EMG, and muscle biopsy, of 5 Chinese patients with SBMA, all males, aged 29 - 58, with the onset age of 36 (17 - 49), were collected the information of in 5 cases. Four patients underwent PCR to examine the number of copies of CAG repeat region in androgen receptor (AR) gene. RESULTS: The clinical characteristics of the 5 patients included atrophy of lingualis, dysarthria, weakness and waste of the limbs, especially in the hands, and elevated creatine kinase (CK), fasting glucose, testosterone, and progesterone in the blood. EMG showed denervation motor potentials in all cases. The muscle biopsy in one case showed neurogenic atrophy. The number of (CAG) n repeat in AR gene was 50 - 62 in the, remarkably from that of 13 normal controls (19 - 20) without overlapping. CONCLUSION: SBMA affects the middle age males, shows a slowly progressing muscular atrophy in spinal and bulbar muscles. The different number of (CAG) n repeat of AR gene between the SBMA patients and the normal controls may be an important identification to differentiate SBMA from other motor neuron diseases.

[Effect of the mutation of promoter region in Wilson disease ATP7B gene on the expression of reporter gene].

OBJECTIVE: To find out the relationship between mutation of ATP7B gene promoter region and pathogenesis of Wilson disease(WD). METHODS: Two of 48 WD patients presented C-->T base substitution mutations at the position -183. DNA sequences of the promoter region from normal and mutant samples were separated. The fragments containing the promoter region were cloned upstream of the luciferase. Luciferase activity was analyzed. RESULTS: The luciferase activity of reporter gene containing normal sequence of ATP7B gene promoter region did not show significant difference as compared with that of reporter gene containing mutant promoter(n=3, P > 0.05). CONCLUSION: No influence of C-->T base substitution mutations on the activity of promoter was observed in study. The results suggest that WD pathogenesis relates little to the mutations of the promoter region in Chinese.

Diminution of toxic copper accumulation in toxic milk mice modeling Wilson disease by embryonic hepatocyte intrasplenic transplantation.

AIM: To observe the therapeutic effect of intrasplenic transplantation with embryonic hepatocytes on amelioration of hereditary copper accumulation in toxic milk (TX) mouse modeling Wilson disease. METHODS: Donor hepatocytes were harvested from 14-d fetal liver of a pregnant homogeneous DL mouse. These cells were successively cultured, labeled with fluorescein dye Hoechst 33342 for 24 h, and sequentially infused into the spleen parenchyma of the recipient TX mice. No host immunosuppression measures were taken. Two and four weeks after transplantation, the recipients were killed for routine histologic investigation and immunohistochemistry study up to 4 wk after transplantation. The serum copper and ceruloplasmin concentrations of the recipient mice were determined by graphite furnace atomic absorption spectroscopy. RESULTS: In the following 2nd and 4th wk after transplantation, the donor hepatocytes could be visualized in the livers of 47.3% recipients. The serum ceruloplasmin and copper concentrations increased by 1.6-fold after 2 wk and 2.0-fold times after 4 wk respectively, which ultimately rose from about 30% of the normal level to nearly 60% (P<0.01). The hepatic copper concentration decreased 7.2%, 4 wk after transplantation. Pathologic examination showed that there were many actively proliferative hepatocyte precursor cells with specific embryonic hepatocyte marker AFP migrated into hepatic sinusoids of the recipients. A large number of cells carrying hepatocytes marker and albumin were observed in the recipient spleen tissues. CONCLUSION: Embryonic hepatocytes are capable of differentiating into mature hepatocytes in vivo. After transplantation, the hereditary abnormalities of copper metabolism in TX mice could be corrected partially by intrasplenic transplantation of homogeneous embryonic hepatocytes.

[Molecular genetics and its clinical application in the diagnosis of spinocerebellar ataxias].

OBJECTIVE: To study the strategy of applying molecular genetic methods and techniques in the diagnosis of spinocerebellar ataxias (SCA). METHODS: This study included 43 patients with SCA from 36 families, 38 sporadic SCA patients, 60 healthy individuals from the SCA families and 44 normal controls. The trinucleotide repeats were detected by polymerase chain reaction (PCR), denaturing polyacrylamide gel electrophoresis and silver staining technique. The repeat numbers were calculated by software. RESULTS: SCA3 was the most common type in the Hans of south China, accounting for 42.0%, followed by SCA2 (7.4%), SCA1 (4.9%), SCA7 (3.7%), SCA6 (2.5%) and SCA12 (1.2%). No patient was found to have SCA8, SCA10, SCA17, and dentatorubro-pallidoluysian atrophy(DRPLA). CONCLUSION: Molecular genetic detection is an effective way to confirmation of SCA subtype diagnosis and presymptomatic genetic diagnosis.

[Molecular genetic diagnosis and clinical analysis of spinocerebellar ataxia type 7].

OBJECTIVE: To study the molecular genetic diagnosis and clinical characteristics of spinocerebellar ataxia type 7 (SCA7). METHODS: This study included 43 patients with autosomal dominant SCA from 36 families, 38 sporadic SCA patients, 60 healthy individuals from the SCA families and 44 normal controls without family SCA history. The SCA7 (CAG)n mutations were detected by PCR, denaturing polyacrylamide gel electrophoresis and silver staining technique. The abnormal allele fragments were sequenced by ABI373 DNA sequencing machine. RESULTS: Normal alleles of SCA7 were found to have 9 to 19 CAG repeats. Two familial SCA and one sporadic patients were identified by detecting the presence of abnormal CAG-repeat expansion in the SCA7 alleles, which was confirmed by DNA sequencing. The repeats of CAG were 65, 65, and 63 respectively. CONCLUSIONS: Abnormal CAG expansion is the pathogenic cause of SCA7. Molecular genetic analysis is effective for the diagnosis of SCA, prediction of presymptomatic patients and genetic counseling.