title: The prevalence of familial hemiplegic migraine with cerebellar ataxia and spinocerebellar ataxia type 6 in Portugal.
abstract: BACKGROUND
  CACNA1A gene disorders present a variable familial phenotype of ataxia, migraine with aura, and/or hemiplegic migraine. Prevalence data for these conditions are scarce.
  
  
  OBJECTIVE
  The aim of this study is to report a minimal prevalence estimate for familial hemiplegic migraine with cerebellar ataxia and spinocerebellar ataxia type 6 in Portugal.
  
  
  METHODS
  This is a multisource population-based prevalence study. Patients and families with spinocerebellar ataxia type 6 and familial hemiplegic migraine and cerebellar ataxia identified through the Portuguese survey of hereditary ataxias and spastic paraplegias were re-evaluated. Prevalent patients were confirmed to be alive and affected at the 1st of January 2013.
  
  
  RESULTS
  One family with spinocerebellar ataxia type 6 and 2 families with other CACNA1A gene mutations were identified. From these families, 23 patients were alive and living in Portugal in the prevalence day, for an estimated national prevalence per 100,000 inhabitants of 0.21 for familial hemiplegic migraine with cerebellar ataxia and of 0.01 for spinocerebellar ataxia type 6.
  
  
  CONCLUSIONS
  The prevalence of familial hemiplegic migraine with cerebellar ataxia and spinocerebellar ataxia type 6 are both probably low in Portugal.
authors.affiliation: Hospital de Santo António, CHP - Centro Hospitalar do Porto, Porto, Portugal; ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal.
authors.forename: José
authors.initials: J
authors.lastname: Barros
authors.forename: Luis
authors.initials: L
authors.lastname: Ruano
authors.forename: Joana
authors.initials: J
authors.lastname: Domingos
authors.forename: Assunção
authors.initials: A
authors.lastname: Tuna
authors.forename: Joana
authors.initials: J
authors.lastname: Damásio
authors.forename: Isabel
authors.initials: I
authors.lastname: Alonso
authors.forename: Isabel
authors.initials: I
authors.lastname: Silveira
authors.forename: Jorge
authors.initials: J
authors.lastname: Sequeiros
authors.forename: Paula
authors.initials: P
authors.lastname: Coutinho
mesh_terms: D015220:Calcium Channels / Q000235:genetics; D002524:Cerebellar Ataxia / Q000150:complications* / Q000453:epidemiology / Q000235:genetics; D018672:Community Health Planning; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D020325:Migraine with Aura / Q000453:epidemiology* / Q000209:etiology* / Q000235:genetics; D009154:Mutation / Q000235:genetics; D011174:Portugal / Q000453:epidemiology; D015995:Prevalence; D020754:Spinocerebellar Ataxias / Q000150:complications* / Q000453:epidemiology / Q000235:genetics; D020864:Calcium Channels, N-Type
chemical_list: D015220:Calcium Channels; C105656:CACNA1A protein, human; D020864:Calcium Channels, N-Type
keywords: CACNA1A; epidemiology; hemiplegic migraine; hereditary ataxia; spinocerebellar ataxia type 6