title: Detection of spinal muscular atrophy carriers in a sample of the Brazilian population.
abstract: BACKGROUND
  Spinal muscular atrophy is a common autosomal recessive neuromuscular disorder caused by mutations in the SMN1 gene. Identification of spinal muscular atrophy carriers has important implications for individuals with a family history of the disorder and for genetic counseling. The aim of this study was to determine the frequency of carriers in a sample of the nonconsanguineous Brazilian population by denaturing high-performance liquid chromatography (DHPLC).
  
  
  METHODS
  To validate the method, we initially determined the relative quantification of DHPLC in 28 affected patients (DHPLC values: 0.00) and 65 parents (DHPLC values: 0.49-0.69). Following quantification, we studied 150 unrelated nonconsanguineous healthy individuals from the general population.
  
  
  RESULTS
  Four of the 150 healthy individuals tested (with no family history of a neuromuscular disorder) presented a DHPLC value in the range of heterozygous carriers (0.6-0.68).
  
  
  CONCLUSIONS
  Based on these results, we estimated there is a carrier frequency of 2.7% in the nonconsanguineous Brazilian population, which is very similar to other areas of the world where consanguineous marriage is not common. This should be considered in the process of genetic counseling and risk calculations.
authors.affiliation: Departments of Neurosciences and Behavior Sciences, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: K C
authors.initials: KC
authors.lastname: Bueno
authors.forename: S P
authors.initials: SP
authors.lastname: Gouvea
authors.forename: A B
authors.initials: AB
authors.lastname: Genari
authors.forename: C A
authors.initials: CA
authors.lastname: Funayama
authors.forename: D L
authors.initials: DL
authors.lastname: Zanette
authors.forename: W A
authors.initials: WA
authors.lastname: Silva
authors.forename: A B
authors.initials: AB
authors.lastname: Oliveira
authors.forename: R H
authors.initials: RH
authors.lastname: Scola
authors.forename: L C
authors.initials: LC
authors.lastname: Werneck
authors.forename: W
authors.initials: W
authors.lastname: Marques
mesh_terms: D000328:Adult; D000368:Aged; D001938:Brazil / Q000208:ethnology; D005260:Female; D005820:Genetic Testing / Q000379:methods; D006579:Heterozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D009134:Muscular Atrophy, Spinal / Q000175:diagnosis / Q000208:ethnology* / Q000235:genetics*; D055533:Survival of Motor Neuron 1 Protein / Q000235:genetics*; D055815:Young Adult
chemical_list: D055533:Survival of Motor Neuron 1 Protein