title: The genome-wide structure of two economically important indigenous Sicilian cattle breeds.
abstract: Genomic technologies, such as high-throughput genotyping based on SNP arrays, provided background information concerning genome structure in domestic animals. The aim of this work was to investigate the genetic structure, the genome-wide estimates of inbreeding, coancestry, effective population size (Ne), and the patterns of linkage disequilibrium (LD) in 2 economically important Sicilian local cattle breeds, Cinisara (CIN) and Modicana (MOD), using the Illumina Bovine SNP50K v2 BeadChip. To understand the genetic relationship and to place both Sicilian breeds in a global context, genotypes from 134 other domesticated bovid breeds were used. Principal component analysis showed that the Sicilian cattle breeds were closer to individuals of Bos taurus taurus from Eurasia and formed nonoverlapping clusters with other breeds. Between the Sicilian cattle breeds, MOD was the most differentiated, whereas the animals belonging to the CIN breed showed a lower value of assignment, the presence of substructure, and genetic links with the MOD breed. The average molecular inbreeding and coancestry coefficients were moderately high, and the current estimates of Ne were low in both breeds. These values indicated a low genetic variability. Considering levels of LD between adjacent markers, the average r(2) in the MOD breed was comparable to those reported for others cattle breeds, whereas CIN showed a lower value. Therefore, these results support the need of more dense SNP arrays for a high-power association mapping and genomic selection efficiency, particularly for the CIN cattle breed. Controlling molecular inbreeding and coancestry would restrict inbreeding depression, the probability of losing beneficial rare alleles, and therefore the risk of extinction. The results generated from this study have important implications for the development of conservation and/or selection breeding programs in these 2 local cattle breeds.
authors.affiliation: Dipartimento di Scienze Agrarie e Forestali, University of Palermo, Viale delle Scienze, 90128 Palermo, Italy salvatore.mastrangelo@unipa.it.
authors.forename: S
authors.initials: S
authors.lastname: Mastrangelo
authors.affiliation: Departamento de Mejora Genética Animal, INIA, Carretera de la Coruña Km 7.5, 28040 Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Saura
authors.affiliation: Dipartimento di Scienze Agrarie e Forestali, University of Palermo, Viale delle Scienze, 90128 Palermo, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Tolone
authors.affiliation: Departamento de Mejora Genética Animal, INIA, Carretera de la Coruña Km 7.5, 28040 Madrid, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Salces-Ortiz
authors.affiliation: Dipartimento di Scienze Agrarie e Forestali, University of Palermo, Viale delle Scienze, 90128 Palermo, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Di Gerlando
authors.affiliation: Department of Agricultural and Food Sciences, Division of Animal Sciences, University of Bologna, Viale Fanin 46, 40127 Bologna, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Bertolini
authors.affiliation: Department of Agricultural and Food Sciences, Division of Animal Sciences, University of Bologna, Viale Fanin 46, 40127 Bologna, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Fontanesi
authors.affiliation: Dipartimento di Scienze Agrarie e Forestali, University of Palermo, Viale delle Scienze, 90128 Palermo, Italy.
authors.forename: M T
authors.initials: MT
authors.lastname: Sardina
authors.affiliation: Departamento de Mejora Genética Animal, INIA, Carretera de la Coruña Km 7.5, 28040 Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Serrano
authors.affiliation: Dipartimento di Scienze Agrarie e Forestali, University of Palermo, Viale delle Scienze, 90128 Palermo, Italy.
authors.forename: B
authors.initials: B
authors.lastname: Portolano
mesh_terms: D000818:Animals; D001947:Breeding; D002417:Cattle / Q000235:genetics*; D040342:Genetic Structures / Q000235:genetics*; D014644:Genetic Variation / Q000235:genetics*; D055106:Genome-Wide Association Study / Q000662:veterinary; D005838:Genotype; D015810:Linkage Disequilibrium / Q000235:genetics; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D012802:Sicily
keywords: Sicilian cattle breeds; genetic diversity; genetic structure; single nucleotide polymorphisms