Child ; Humans ; Male ; Spinocerebellar Ataxias ; diagnosis

PURPOSE: Spinocerebellar ataxia (SCA) is a genetically heterogeneous disease for which more than 30 subtypes have been identified. However, 5 subtypes, SCA1, SCA2, SCA3, SCA6, and SCA7, account for more than 60% of cases. In this study, we report the distribution of these 5 subtypes in Korean patients. MATERIALS AND METHODS: Six hundred and thirty-eight unrelated patients with a presumptive diagnosis of SCA were included in this study. Trinucleotide (CAG) repeat number (TNR) repeat number was determined using fluorescently labeled primers and fragment analysis. RESULTS: A total of 128 unrelated patients (20.1% of all individuals tested) tested positive for SCA subtypes, including SCA1 (5 patients, 3.9% of those testing positive), SCA2 (38 patients, 29.7%), SCA3 (30 patients, 23.4%), SCA6 (39 patients, 30.5%), and SCA7 (16 patients, 12.5%). The mean copy number of pathogenic TNR alleles was 45+/-8.5 for SCA1, 42+/-3.1 for SCA2, 72+/-5.4 for SCA3, 23+/-1.5 for SCA6, and 50+/-11.4 for SCA7. TNR copy number was inversely correlated with onset age in SCA2, SCA6, and SCA7. CONCLUSION: SCA2, SCA3, and SCA6 are common SCA subtypes in Korean patients and could be screened as a first-line test. Expanded pathogenic allele size was associated with early onset age.
Age of Onset ; Alleles ; Diagnosis ; Humans ; Spinocerebellar Ataxias* ; Trinucleotide Repeats

Studies on spinocerebellar ataxias (SCA) have been hampered by a lack of disease markers. Clinical and pathological heterogeneity also made the classification unreliable. Linkage studies established that there are multiple subtypes of SCA. Five types are found to have unstable CAG expansion; the diagnosis can be established by molecular genetic study. Therefore, we systemically screened degenerative ataxia patients for these five SCA types, and identified eight patients with SCA2 (seven from six families and one sporadic case). This paper presents the clinical information on the seven patients, whose clinical information was available in detail. CAG repeat expansion in the patients ranged from 38 to 47 (normal control, 19 to 27). The onset ages ranged from 16 to 41 with 27.1 years as the mean, which correlated inversely with repeat lengths. All patients presented dysarthria and gait ataxia. Upper limb dysmetria or dysdiadochokinesia appeared later but progressed, causing severe disability. Slow saccade (4 patients in 7) and decreased DTR (4 in 7) were common. MRIs showed severe atrophy of the brainstem and cerebellum in all patients. We conclude that SCA2 is the most frequent type in Korea and carries rather pure cerebellar syndrome, slow saccade, and hyporeflexia.
Adolescence ; Adult ; Age of Onset ; Brain/pathology ; DNA Mutational Analysis ; Female ; Human ; Korea ; Lymphocytes ; Magnetic Resonance Imaging ; Male ; Spinocerebellar Ataxias/genetics* ; Spinocerebellar Ataxias/diagnosis ; Spinocerebellar Ataxias/blood ; Trinucleotide Repeats/genetics*

Adolescent ; Adult ; Child ; Female ; Humans ; Male ; Pedigree ; Spinocerebellar Ataxias ; diagnosis ; genetics ; Young Adult

Previously, we defined DRD as a syndrome of selective nigrostriatal dopamine deficiency caused by genetic defects in the dopamine synthetic pathway without nigral cell loss. DRD-plus also has the same etiologic background with DRD, but DRD-plus patients have more severe features that are not seen in DRD because of the severity of the genetic defect. However, there have been many reports of dystonia responsive to dopaminergic drugs that do not fit into DRD or DRD-plus (genetic defects in the dopamine synthetic pathway without nigral cell loss). We reframed the concept of DRD/DRD-plus and proposed the concept of DRD look-alike to include the additional cases described above. Examples of dystonia that is responsive to dopaminergic drugs include the following: transportopathies (dopamine transporter deficiency; vesicular monoamine transporter 2 deficiency); SOX6 mutation resulting in a developmentally decreased number of nigral cells; degenerative disorders with progressive loss of nigral cells (juvenile Parkinson's disease; pallidopyramidal syndrome; spinocerebellar ataxia type 3), and disorders that are not known to affect the nigrostriatal dopaminergic system (DYT1; GLUT1 deficiency; myoclonus-dystonia; ataxia telangiectasia). This classification will help with an etiologic diagnosis as well as planning the work up and guiding the therapy.
Ataxia ; Classification ; Diagnosis ; Dopamine ; Dopamine Agents ; Dystonia* ; Humans ; Parkinson Disease ; Spinocerebellar Ataxias ; Vesicular Monoamine Transport Proteins

Central Nervous System Diseases ; diagnosis ; genetics ; Fragile X Syndrome ; genetics ; Genotype ; Humans ; Molecular Biology ; Phenotype ; Spinocerebellar Ataxias ; diagnosis ; genetics ; Syndrome

Clinically, multiple system atrophy is difficult to differentiate from other basal ganglia disorders such as idiopathic Parkinson's disease or other types of cerebellar ataxia. The "hot cross bun"sign is a radiological sign which, it has been claimed, is highly specific for multiple system atrophy, and we describe four cases in which this sign occurred. In one patient, multiple system atrophy was clinically diagnosed, but in the other three, the respective clinical diagnosis was spinocerebellar ataxia type 1, type 2 (genetically), and old cerebellar hemorrhage. We therefore suggest that the hot cross bun sign reflects degeneration of transverse pontocerebellar fibers and is not a pathognomic sign of multiple system atrophy.
Basal Ganglia Diseases ; Cerebellar Ataxia ; Diagnosis ; Hemorrhage ; Humans ; Magnetic Resonance Imaging* ; Movement Disorders* ; Multiple System Atrophy ; Parkinson Disease ; Spinocerebellar Ataxias

OBJECTIVETo study the strategy of applying molecular genetic methods and techniques in the diagnosis of spinocerebellar ataxias (SCA).

METHODSThis 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.

RESULTSSCA3 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).

CONCLUSIONMolecular genetic detection is an effective way to confirmation of SCA subtype diagnosis and presymptomatic genetic diagnosis.

Adult ; Electrophoresis, Polyacrylamide Gel ; Female ; Humans ; Male ; Middle Aged ; Pedigree ; Polymerase Chain Reaction ; Spinocerebellar Ataxias ; diagnosis ; genetics ; Trinucleotide Repeats ; genetics

BACKGROUND AND PURPOSE: The etiologies and frequencies of cerebellar ataxias vary between countries. Our primary aim was to determine the frequency of each diagnostic group of cerebellar ataxia patients in a Korean population. METHODS: We reviewed the medical records of patients who were being followed up between November 1994 and February 2016. We divided patients with cerebellar ataxias into familial and non-familial groups and analyzed the frequency of each etiology. Finally, we categorized patients into genetic, sporadic, secondary, and suspected genetic, but undetermined ataxia. RESULTS: A total of 820 patients were included in the study, among whom 136 (16.6%) familial patients and 684 (83.4%) non-familial cases were identified. Genetic diagnoses confirmed 98/136 (72%) familial and 72/684 (11%) nonfamilial patients. The overall etiologies of progressive ataxias comprised 170 (20.7%) genetic, 516 (62.9%) sporadic, 43 (5.2%) secondary, and 91 (11.1%) undetermined ataxia. The most common cause of ataxia was multiple-system atrophy (57.3%). In the genetic group, the most common etiology was spinocerebellar ataxia (152/170, 89.4%) and the most common subtype was spinocerebellar ataxia-3.38 of 136 familial and 53 of 684 sporadic cases (91/820, 11.1%) were undetermined ataxia. CONCLUSIONS: This is the largest epidemiological study to analyze the frequencies of various cerebellar ataxias in a Korean population based on the large database of a tertiary hospital movement-disorders clinic in South Korea. These data would be helpful for clinicians in constructing diagnostic strategies and counseling for patients with cerebellar ataxias.
Ataxia ; Atrophy ; Cerebellar Ataxia* ; Counseling ; Diagnosis ; Epidemiologic Studies ; Friedreich Ataxia ; Humans ; Korea ; Medical Records ; Spinocerebellar Ataxias ; Tertiary Care Centers

OBJECTIVE: Diagnosis of sporadic cerebellar ataxia is a challenge for neurologists. A wide range of potential causes exist, including chronic alcohol use, multiple system atrophy of cerebellar type (MSA-C), and sporadic late cortical cerebellar atrophy. Recently, an autosomal-dominant spinocerebellar ataxia (SCA) mutation was identified in a cohort of patients with non-MSA-C sporadic cerebellar ataxia. The aim of this study is to genetically screen genes involved in SCA in a Japanese single-hospital cohort. METHODS: Over an 8-year period, 140 patients with cerebellar ataxia were observed. There were 109 patients with sporadic cerebellar ataxia (no family history for at least four generations, 73 patients with MSA-C, and 36 patients with non-MSA-C sporadic cerebellar ataxia) and 31 patients with familial cerebellar ataxia. We performed gene analysis comprising SCA1, 2, 3, 6, 7, 8, 12, 17, 31, and dentatorubro-pallidoluysian atrophy (DRPLA) in 28 of 31 non-MSA-C sporadic patients who requested the test. Familial patients served as a control. RESULTS: Gene abnormalities were found in 57% of non-MSA-C sporadic cerebellar ataxia cases. Among patients with sporadic cerebellar ataxia, abnormalities in SCA6 were the most common (36%), followed by abnormalities in SCA1 (7.1%), SCA2 (3.6%), SCA3 (3.6%), SCA8 (3.6%), and DRPLA (3.6%). In contrast, gene abnormalities were found in 75% of familial cerebellar ataxia cases, with abnormalities in SCA6 being the most common (29%). For sporadic versus familial cases for those with SCA6 abnormalities, the age of onset was older (69 years vs. 59 years, respectively), and CAG repeat length was shorter (23 vs. 25, respectively) in the former than in the latter (not statistically significant). CONCLUSION: Autosomal-dominant mutations in SCA genes, particularly in SCA6, are not rare in sporadic cerebellar ataxia. The reason for the frequency of mutations in SCA6 remains unclear; however, the reason may reflect a higher age at onset and variable penetrance of SCA6 mutations.
Age of Onset ; Asian Continental Ancestry Group* ; Atrophy ; Cerebellar Ataxia ; Cohort Studies* ; Diagnosis ; Family Characteristics ; Genetic Testing* ; Heredity ; Humans ; Multiple System Atrophy ; Penetrance ; Spinocerebellar Ataxias*