title: Strong association of socioeconomic status with genetic ancestry in Latinos: implications for admixture studies of type 2 diabetes.
abstract: OBJECTIVE
  Type 2 diabetes is more prevalent in US American minority populations of African or Native American descent than it is in European Americans. However, the proportion of this epidemiological difference that can be ascribed to genetic or environmental factors is unknown. To determine whether genetic ancestry is correlated with diabetes risk in Latinos, we estimated the proportion of European ancestry in case-control samples from Mexico and Colombia in whom socioeconomic status had been carefully ascertained.
  
  
  METHODS
  We genotyped 67 ancestry-informative markers in 499 participants with type 2 diabetes and 197 controls from Medellín (Colombia), as well as in 163 participants with type 2 diabetes and 72 controls from central Mexico. Each participant was assigned a socioeconomic status scale via various measures.
  
  
  RESULTS
  Although European ancestry was associated with lower diabetes risk in Mexicans (OR [95% CI] 0.06 [0.02-0.21], p = 2.0 x 10(-5)) and Colombians (OR 0.26 [0.08-0.78], p = 0.02), adjustment for socioeconomic status eliminated the association in the Colombian sample (OR 0.64 [0.19-2.12], p = 0.46) and significantly attenuated it in the Mexican sample (OR 0.17 [0.04-0.71], p = 0.02). Adjustment for BMI did not change the results.
  
  
  CONCLUSIONS
  The proportion of non-European ancestry is associated with both type 2 diabetes and lower socioeconomic status in admixed Latino populations from North and South America. We conclude that ancestry-directed search for genetic markers associated with type 2 diabetes in Latinos may benefit from information involving social factors, as these factors have a quantitatively important effect on type 2 diabetes risk relative to ancestry effects.
authors.affiliation: Department of Medicine, Harvard Medical School, Boston, MA, USA, jcflorez@partners.org.
authors.forename: J C
authors.initials: JC
authors.lastname: Florez
authors.forename: A L
authors.initials: AL
authors.lastname: Price
authors.forename: D
authors.initials: D
authors.lastname: Campbell
authors.forename: L
authors.initials: L
authors.lastname: Riba
authors.forename: M V
authors.initials: MV
authors.lastname: Parra
authors.forename: F
authors.initials: F
authors.lastname: Yu
authors.forename: C
authors.initials: C
authors.lastname: Duque
authors.forename: R
authors.initials: R
authors.lastname: Saxena
authors.forename: N
authors.initials: N
authors.lastname: Gallego
authors.forename: M
authors.initials: M
authors.lastname: Tello-Ruiz
authors.forename: L
authors.initials: L
authors.lastname: Franco
authors.forename: M
authors.initials: M
authors.lastname: Rodríguez-Torres
authors.forename: A
authors.initials: A
authors.lastname: Villegas
authors.forename: G
authors.initials: G
authors.lastname: Bedoya
authors.forename: C A
authors.initials: CA
authors.lastname: Aguilar-Salinas
authors.forename: M T
authors.initials: MT
authors.lastname: Tusié-Luna
authors.forename: A
authors.initials: A
authors.lastname: Ruiz-Linares
authors.forename: D
authors.initials: D
authors.lastname: Reich
mesh_terms: D003105:Colombia / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000191:economics / Q000453:epidemiology* / Q000235:genetics; D006630:Hispanic or Latino / Q000706:statistics & numerical data*; D006801:Humans; D008800:Mexico / Q000453:epidemiology; D044469:Racial Groups / Q000706:statistics & numerical data; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology; D044465:White People