title: Iris texture traits show associations with iris color and genomic ancestry.
abstract: OBJECTIVE
  This study seeks to identify associations among genomic biogeographic ancestry (BGA), quantitative iris color, and iris texture traits contributing to population-level variation in these phenotypes.
  
  
  METHODS
  DNA and iris photographs were collected from 300 individuals across three variably admixed populations (Portugal, Brazil, and Cape Verde). Two raters scored the photos for pigmentation spots, Fuchs' crypts, contraction furrows, and Wolflinn nodes. Iris color was quantified from RGB values. Maximum likelihood estimates of individual BGA were calculated from 176 ancestry informative markers.
  
  
  RESULTS
  Pigmentation spots, Fuchs' crypts, contraction furrows, and iris color show significant positive correlation with increasing European BGA. Only contraction furrows are correlated with iris color.
  
  
  CONCLUSIONS
  The relationship between BGA and iris texture illustrates a genetic contribution to this population-level variation.
authors.affiliation: Department of Anthropology, Pennsylvania State University, University Park, 16802, USA. equillen@sfbrgenetics.org
authors.forename: Ellen E
authors.initials: EE
authors.lastname: Quillen
authors.forename: Jenna S
authors.initials: JS
authors.lastname: Guiltinan
authors.forename: Sandra
authors.initials: S
authors.lastname: Beleza
authors.forename: Jorge
authors.initials: J
authors.lastname: Rocha
authors.forename: Rinaldo W
authors.initials: RW
authors.lastname: Pereira
authors.forename: Mark D
authors.initials: MD
authors.lastname: Shriver
mesh_terms: D001938:Brazil; D055726:Cabo Verde; D004247:DNA / Q000032:analysis; D023281:Genomics / Q000706:statistics & numerical data*; D006801:Humans; D007498:Iris / Q000033:anatomy & histology* / Q000502:physiology; D016013:Likelihood Functions; D010641:Phenotype; D010781:Photography; D058974:Phylogeography; D011174:Portugal; D012044:Regression Analysis; D013223:Statistics as Topic
chemical_list: D004247:DNA