title: Importance of the geographic barriers to promote gene drift and avoid pre- and post-Columbian gene flow in Mexican native groups: Evidence from forensic STR Loci.
abstract: OBJECTIVE
  To analyze the origin, structure, relationships, and recent admixture in Mexican Native groups based on 15 STRs commonly used in human identification.
  
  
  METHODS
  We analyzed 39 Mexican Native population samples using STR databases based on the AmpFlSTR® Identifiler kit (n = 3,135), including Mexican-Mestizos (admixed), European and African populations, as reference.
  
  
  RESULTS
  Based upon effective population size (Ne) differences, Native groups were clustered into three regions: i) Center-Southeast groups, characterized by larger Ne, migration rate (Nm), genetic diversity (He), and relative homogeneity principally in the Yucatan Peninsula; ii) Isolated southern groups from Chiapas and Oaxaca, characterized by lower Ne, Nm, and He (i.e. higher isolation and genetic differentiation); iii) North-Northwest groups, which are similar to the previous group but are characterized by generating the widest gene flow barrier in the Pre-Hispanic Mexican territory, and currently by elevated admixture in some northern Native groups. Despite the relative congruence between genetic relationships with cultural, linguistic, geographic criteria, these factors do not explain the present-day population structure of Native groups, excepting in those linguistically related to the Mayan that show higher homogeneity. The Isolation by distance model was demonstrated at long distances (>1,500 km), whereas geographic isolation stands as a determining factor to avoid both non-indigenous admixture and bottleneck processes.
  
  
  CONCLUSIONS
  Different dynamics of gene flow and drift were observed among Mexican Native groups, highlighting the geographic barriers (mountains, canyons and jungle regions) as the main factor differentiating Pre-Hispanic populations, and eventually helping to avoid Post-European contact admixture and population bottleneck. Am J Phys Anthropol 160:298-316, 2016. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Instituto De Investigación En Genética Molecular, Centro Universitario De La Ciénega (CUCI-UdeG), Ocotlán, Jalisco, México.
authors.forename: Héctor
authors.initials: H
authors.lastname: Rangel-Villalobos
authors.affiliation: Instituto De Investigación En Genética Molecular, Centro Universitario De La Ciénega (CUCI-UdeG), Ocotlán, Jalisco, México.
authors.forename: Víctor Manuel
authors.initials: VM
authors.lastname: Martínez-Sevilla
authors.affiliation: Instituto De Investigación En Genética Molecular, Centro Universitario De La Ciénega (CUCI-UdeG), Ocotlán, Jalisco, México.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Martínez-Cortés
authors.affiliation: Instituto De Investigación En Genética Molecular, Centro Universitario De La Ciénega (CUCI-UdeG), Ocotlán, Jalisco, México.
authors.forename: José Alonso
authors.initials: JA
authors.lastname: Aguilar-Velázquez
authors.affiliation: Unidad Durango (CIIDIR-IPN), Centro Interdisciplinario De Investigación Para El Desarrollo Integral Regional Del Instituto Politécnico Nacional, Durango, México.
authors.forename: Martha
authors.initials: M
authors.lastname: Sosa-Macías
authors.affiliation: Laboratorio De Genética, Centro De Investigaciones Regionales Hideyo Noguchi, Universidad Autónoma De Yucatán (UADY), Mérida, Yucatán.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Rubi-Castellanos
authors.affiliation: Departamento De Zoología Y Antropología Física, Facultad De Biología, Universidad Complutense De Madrid, Madrid, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: González-Martín
mesh_terms: D051456:Gene Flow / Q000235:genetics*; D040961:Genetic Drift; D014644:Genetic Variation; D005828:Genetics, Population; D006801:Humans; D007198:Indians, North American / Q000145:classification / Q000235:genetics*; D008800:Mexico; D018895:Microsatellite Repeats / Q000235:genetics*; D010802:Phylogeny
keywords: Amerindians; Mexico; STRs; admixture; gene drift; structure