Assessing the genetic diversity and ancestry of Hartón del Valle cattle using mitochondrial DNA ¤ Diversidad genética y ancestría del ganado Hartón del Valle mediante ADN mitocondrial Estimação da ancestralidade e da diversidade genética no gado Hartón del Valle utilizando DNA mitocondrial

Summary The Harton del Valle (HV) cattle is a Criollo breed of Spanish descent that has adapted to the conditions of the Cauca valley (Colombia). This breed is currently listed as “vulnerable” because its population has dramatically declined in the last two years. Prompted by the uncertain future of this breed and its importance as a potential resource of valuable genes. Objective: this study addressed the diversity, genetic structure and ancestry of HV cattle using mitochondrial DNA (mtDNA). Methods: a 350-bp fragment was amplified and sequenced from 72 HV animals in 9 separate farms and from animals of Brahman and Holstein breeds. To analyze the breed’s ancestry, the sequences were compared with 560 sequences available in the GenBank, representing 50 Bos taurus and Bos indicus breeds. Results: in accordance with the Spanish origin of the HV breed, there was a high representation of European mtDNA (91.7%) and a low representation of African (5.5%) and Middle Eastern mtDNA (2.7%). The average haplotype diversity was 0.65 ± 0.05. The farm with the oldest ancestry was the only population in which three mitochondrial lineages were observed; unfortunately, it was recently depopulated. Proximity was observed between HV and two Columbian breeds, the Romosinuano and Costeno con Cuernos. A comparative analysis with the sequences deposited in the GenBank from numerous breeds revealed the presence of 37 haplotypes, seven of which were unique to HV. Conclusions: the following Iberian breeds were found to be most closely related to HV: Tudanca, Rubia Gallega, Negra Serrana, Murciana, Pajuna, Avilena, Garvonesa and Mertolenga. Phylogenetic analysis confirmed the Iberian ancestry and some African influence on this Latin American Criollo breed.