D-loop haplotype diversity in Brazilian horse breeds

• Published in: Genetics and molecular biology Vol. 40; no. 3; pp. 604 - 609
• Main Authors: Ianella, Patrícia, Albuquerque, Maria do Socorro Maués, Paiva, Samuel Rezende, Egito, Andréa Alves do, Almeida, Leonardo Daniel, Sereno, Fabiana T P S, Carvalho, Luiz Felipe Ramos, Mariante, Arthur da Silva, McManus, Concepta Margaret
• Format: Journal Article
• Language: English
• Published: Brazil Sociedade Brasileira de Genetica 01-07-2017; Sociedade Brasileira de Genética
• Subjects: animal genetic resources; Animal Genetics; BIOCHEMISTRY & MOLECULAR BIOLOGY; Decision making; Environmental conditions; Equus caballus; Gene sequencing; genetic characterization; Genetic diversity; GENETICS & HEREDITY; Haplotypes; Horses; locally adapted breeds; mitochondrial DNA; Brazil; Equus caballus; mitochondrial DNA; locally adapted breeds; genetic characterization; animal genetic resources
• ISSN: 1415-4757; 1678-4685; 1678-4685
• DOI: 10.1590/1678-4685-GMB-2016-0166

The first horses were brought to Brazil by the colonizers after 1534. Over the centuries, these animals evolved and adapted to local environmental conditions usually unsuitable for exotic breeds, thereby originating locally adapted Brazilian breeds. The present work represents the first description of maternal genetic diversity in these horse breeds based on D-loop sequences. A D-Loop HSV-I fragment of 252 bp, from 141 horses belonging to ten Brazilian breeds / genetic groups (locally adapted and specialized breeds) were analysed. Thirty-five different haplotypes belonging to 18 haplogroups were identified with 33 polymorphic sites. Haplotype diversity (varying from 0.20 to 0.96) and nucleotide diversity (varying from 0.0039 to 0.0239) was lower for locally adapted than for specialized breeds, with the same pattern observed for FST values. Haplogroups identified in Brazilian breeds are in agreement with previous findings in South American samples. The low variability observed mainly in locally adapted breeds, indicates that, to ensure conservation of these breeds, careful reproductive management is needed. Additional genetic characterization studies are required to support accurate decision-making.