title: Amerindian genetic ancestry protects against Alzheimer's disease.
abstract: BACKGROUND
  Alzheimer's disease (AD) is the most common form of dementia worldwide, and bears remarkable evidence for a differential prevalence among continental populations. In this scenario, estimating ancestry proportions in recently admixed populations is a strategy that can help increasing knowledge about the genetic structure of this complex trait.
  
  
  OBJECTIVE
  Our purpose was to assess mean ancestry estimates for the three main parental contributors to the Brazilian contingent (European, African and Amerindian) using a panel of 12 ancestry informative markers. Outpatients with the late-onset form of AD (n = 120) were compared for ancestry levels with non-cognitively impaired subjects (n = 412) in the Midwest Brazil, controlling for classic clinical, social and anthropometric risk factors.
  
  
  RESULTS
  Our findings show a 3-fold greater genetic Amerindian content among control subjects compared to AD patients (p < 0.001).
  
  
  CONCLUSIONS
  Our results suggest that the allelic architecture of Native Americans can confer protection against the onset of the disease.
authors: Programa de Pós-Graduação em Ciências Médicas, Universidade de Brasília, Brasília, DF, Brazil.
authors: Andrea L
authors: AL
authors: Benedet
authors: Clayton F
authors: CF
authors: Moraes
authors: Einstein F
authors: EF
authors: Camargos
authors: Larissa F
authors: LF
authors: Oliveira
authors: Vinícius C
authors: VC
authors: Souza
authors: Túlio C
authors: TC
authors: Lins
authors: Adriane D
authors: AD
authors: Henriques
authors: Dayanne G S
authors: DG
authors: Carmo
authors: Wilcelly
authors: W
authors: Machado-Silva
authors: Carla Nunes
authors: CN
authors: Araújo
authors: Cláudio
authors: C
authors: Córdova
authors: Rinaldo W
authors: RW
authors: Pereira
authors: Otávio T
authors: OT
authors: Nóbrega
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000235:genetics*; D053327:Apolipoprotein E4 / Q000235:genetics; D044383:Black People / Q000235:genetics*; D001938:Brazil; D016022:Case-Control Studies; D005260:Female; D005787:Gene Frequency; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007199:Indians, South American / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D044465:White People / Q000235:genetics*
chemical_list: D053327:Apolipoprotein E4; D005819:Genetic Markers