title: Genomic variation and population structure detected by single nucleotide polymorphism arrays in Corriedale, Merino and Creole sheep.
abstract: THE AIM OF THIS STUDY WAS TO INVESTIGATE THE GENETIC DIVERSITY WITHIN AND AMONG THREE BREEDS OF SHEEP: Corriedale, Merino and Creole. Sheep from the three breeds (Merino n = 110, Corriedale n = 108 and Creole n = 10) were genotyped using the Illumina Ovine SNP50 beadchip(®). Genetic diversity was evaluated by comparing the minor allele frequency (MAF) among breeds. Population structure and genetic differentiation were assessed using STRUCTURE software, principal component analysis (PCA) and fixation index (FST). Fixed markers (MAF = 0) that were different among breeds were identified as specific breed markers. Using a subset of 18,181 single nucleotide polymorphisms (SNPs), PCA and STUCTURE analysis were able to explain population stratification within breeds. Merino and Corriedale divergent lines showed high levels of polymorphism (89.4% and 86% of polymorphic SNPs, respectively) and moderate genetic differentiation (FST = 0.08) between them. In contrast, Creole had only 69% polymorphic SNPs and showed greater genetic differentiation from the other two breeds (FST = 0.17 for both breeds). Hence, a subset of molecular markers present in the OvineSNP50 is informative enough for breed assignment and population structure analysis of commercial and Creole breeds.
authors: Meat and Wool National Program , Instituto Nacional de Investigación Agropecuaria , Las Brujas, Canelones , Uruguay .
authors: Andrés N
authors: AN
authors: Grasso
authors: Meat and Wool National Program , Instituto Nacional de Investigación Agropecuaria , Las Brujas, Canelones , Uruguay .
authors: Virginia
authors: V
authors: Goldberg
authors: Biotechnology Unit , Instituto Nacional de Investigación Agropecuaria , Las Brujas, Canelones , Uruguay .
authors: Elly A
authors: EA
authors: Navajas
authors: Biotechnology Unit , Instituto Nacional de Investigación Agropecuaria , Las Brujas, Canelones , Uruguay .
authors: Wanda
authors: W
authors: Iriarte
authors: Department of Animal Genetic Improvement , Secretariado Uruguayo de la Lana , Montevideo , Uruguay .
authors: Diego
authors: D
authors: Gimeno
authors: Meat and Wool National Program , Instituto Nacional de Investigación Agropecuaria , Las Brujas, Canelones , Uruguay .
authors: Ignacio
authors: I
authors: Aguilar
authors: Department of Animal Science , University of California Davis , USA .
authors: Juan F
authors: JF
authors: Medrano
authors: Department of Animal Science , University of California Davis , USA .
authors: Gonzalo
authors: G
authors: Rincón
authors: Meat and Wool National Program , Instituto Nacional de Investigación Agropecuaria , Las Brujas, Canelones , Uruguay .
authors: Gabriel
authors: G
authors: Ciappesoni
keywords: Ovine SNP50; allele frequencies breed composition; fixation index; population stratification; principal component analysis