Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042571 (vertigo)
 7,148 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present authors studied a 55-year-old-patient homozygous for the SCA6 gene who experienced frequent attacks of positional vertigo at 37 years of age with subsequent staggering gait and night blindness. Retinitis pigmentosa (RP), as well as cerebellar ataxia and vertical antidirectional nystagmus, were detected. The subject's parents were first cousins, and two of his three male cousins, whose parents were also first cousins, had RP without ataxia or nystagmus. The numbers of CAG repeats in the expanded alleles of the SCA6 gene found by molecular analysis were 21 and 21. The genetic results were negative for SCA1, SCA2, SCA3, SCA7 and dentatorubral pallidoluysian atrophy. The retinal degeneration in this patient is most likely to be secondary to a genetic disorder of autosomal or X-linked recessive inheritance rather than SCA6. Other reported cases of patients homozygous for the SCA6 gene are also reviewed.
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PMID:A patient homozygous for the SCA6 gene with retinitis pigmentosa. 1208 23

Spinocerebellar ataxia (SCA) is a group of heterogeneous disorders. In Japan, approximately 60% of SCA consist of sporadic disorders, and the rest mostly consists of a variety of late-onset dominant disorders. In the latter, MJD, SCA6, DRPLA, SCA1 and SCA2 are frequent in this order, and others are rare. All these disorders are caused by unstable expansion of CAG repeat in the coding region of each responsible gene. Among those disorders, SCA6 manifests late-onset pure cerebellar ataxia and frequently associated with positioning vertigo. In other disorders, phenotype variation, clinical severity, and onset of age are known to correlate inversely with the CAG repeat size. Such variation even in a given disorder is often difficult to apply single criteria to diagnose the disorder based on its clinical findings alone. MSA is a major disorder of sporadic SCA. Signs of cerebellar ataxia, parkinsonism, autonomic disturbance are incorporated into current diagnostic criteria. However, cases meeting the criteria of autonomic disturbances are confined to the advanced stage of the illness or rare cases starting with obvious dysautonomia. These problems indicate that the criteria need further adjustment.
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PMID:[Differential diagnosis of spinocerebellar ataxia]. 1278 68

In order to clarify the clinical and genetic features of SCA6, we retrospectively analyzed 140 patients. We observed an inverse correlation between the age of onset and the length of the expanded allele, and also between the age of onset and the sum of CAG repeats in the normal and the expanded alleles. The ages of onset of four homozygous patients correlated better with the sum of CAG repeats in both alleles rather than with the expanded allele calculated from heterozygous SCA6 subjects. Clinically, unsteadiness of gait was the main initial symptom, followed by vertigo and oscillopsia, and cerebellar signs were detected in nearly 100% of the patients. In contrast, extracerebellar signs were relatively mild and infrequent. The results of neuro-otological examination performed in 22 patients suggested the purely cerebellar abnormalities of ocular movements in nature. There was a close relationship between downbeat positioning nystagmus (DPN) and positioning vertigo, which became more common in the later stage. We conclude that total number of CAG repeat-units in both alleles is a good parameter for assessment of age of onset in SCA6 including homozygous patients. In addition, clinical and neuro-otological examinations suggested that SCA6 is a disease with predominantly cerebellar dysfunction.
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PMID:A clinical and genetic study in a large cohort of patients with spinocerebellar ataxia type 6. 1536 69

Onset of genetically determined neurodegenerative diseases is difficult to specify because of their insidious and slowly progressive nature. This is especially true for spinocerebellar ataxia (SCA) because of varying affection of many parts of the nervous system and huge variability of symptoms. We investigated early symptoms in 287 patients with SCA1, SCA2, SCA3, or SCA6 and calculated the influence of CAG repeat length on age of onset depending on (1) the definition of disease onset, (2) people defining onset, and (3) duration of symptoms. Gait difficulty was the initial symptom in two-thirds of patients. Double vision, dysarthria, impaired hand writing, and episodic vertigo preceded ataxia in 4% of patients, respectively. Frequency of other early symptoms did not differ from controls and was regarded unspecific. Data about disease onset varied between patients and relatives for 1 year or more in 44% of cases. Influence of repeat length on age of onset was maximum when onset was defined as beginning of permanent gait disturbance and cases with symptoms for more than 10 years were excluded. Under these conditions, CAG repeat length determined 64% of onset variability in SCA1, 67% in SCA2, 46% in SCA3, and 41% in SCA6 demonstrating substantial influence of nonrepeat factors on disease onset in all SCA subtypes. Identification of these factors is of interest as potential targets for disease modifying compounds. In this respect, recognition of early symptoms that develop before onset of ataxia is mandatory to determine the shift from presymptomatic to affected status in SCA.
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PMID:Early symptoms in spinocerebellar ataxia type 1, 2, 3, and 6. 1875 44