title: Low familial risks for multiple sclerosis in Buenos Aires, Argentina.
abstract: BACKGROUND
  Multiple sclerosis is a complex disease in which genetic susceptibility plays a role and familial occurrence has long been recognized. To date, no studies of familial occurrence have been conducted in Argentina, a country with low to intermediate prevalence.
  
  
  METHODS
  As part of a cross-sectional study on multiple sclerosis in Buenos Aires, immediate and extended pedigree details were collected on 219 patients. Crude and age-adjusted recurrence risks for patient relatives were also assessed.
  
  
  RESULTS
  Details on age or age of death and disease status were obtained for 4227 relatives. Ten percent of patients reported at least one relative with MS diagnosis, the highest risk (1.54%) was observed in daughters of patients who presented 92-times greater risk than the general population. Sibling recurrence risk ratio was similar to that reported in other locations.
  
  
  CONCLUSIONS
  Relatives of patients with MS living in Argentina are at greater risk of developing the disease, although not as high as the risk reported for other geographic regions.
authors.affiliation: Department of Neurology, Raúl Carrea Institute for Neurological Research (FLENI), Buenos Aires, Argentina.
authors.forename: Mauricio F
authors.initials: MF
authors.lastname: Farez
authors.affiliation: Department of Neurology, Raúl Carrea Institute for Neurological Research (FLENI), Buenos Aires, Argentina; Department of Neurology, Hospital de Clínicas José de San Martín, Buenos Aires, Argentina.
authors.forename: María E
authors.initials: ME
authors.lastname: Balbuena Aguirre
authors.affiliation: Department of Neurology, Raúl Carrea Institute for Neurological Research (FLENI), Buenos Aires, Argentina.
authors.forename: Francisco
authors.initials: F
authors.lastname: Varela
authors.affiliation: Department of Neurology, Raúl Carrea Institute for Neurological Research (FLENI), Buenos Aires, Argentina.
authors.forename: Alejandro A
authors.initials: AA
authors.lastname: Köhler
authors.affiliation: Department of Neurology, Raúl Carrea Institute for Neurological Research (FLENI), Buenos Aires, Argentina.
authors.forename: Vanesa
authors.initials: V
authors.lastname: Nagel
authors.affiliation: Department of Neurology, Raúl Carrea Institute for Neurological Research (FLENI), Buenos Aires, Argentina. Electronic address: jcorreale@fleni.org.ar.
authors.forename: Jorge
authors.initials: J
authors.lastname: Correale
mesh_terms: D000328:Adult; D001118:Argentina / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000453:epidemiology / Q000235:genetics*; D010375:Pedigree; D015995:Prevalence; D012307:Risk Factors
keywords: Argentina; Familial risk; Multiple sclerosis; Recurrence risk; Sibling recurrence-risk; South America