Search Results (3)

This Systematic Literature Review (SLR) consolidates current research on mitochondrial DNA (mtDNA) analysis in horses, focusing on genetic variation, maternal lineage tracing, and haplogroup identification. The article selection process screened 1380 articles, with 76 fulfilling the inclusion criteria. Data extraction covered sampling techniques, studied mtDNA regions, sequencing methods, and haplogroup identification. Following the methodology of the PRISMA guidelines, this review encompasses studies published since 2012, obtained from Scopus, PubMed, Research4Life, Web of Science, and ScienceDirect. The major findings emphasise the use of mtDNA for tracing ancestry, validating maternal lineages, and identifying haplogroups along with their geographic distributions. This review identifies challenges, including the need to update the haplogroup classification system and potential information loss due to sequence trimming. Additionally, it examines promising avenues for future research, such as the implementation of next-generation sequencing and the merging of haplogroup data with performance traits, which could influence conservation initiatives and breeding programs. This review emphasises the necessity for standardised classification systems and further research on underrepresented breeds and regions to improve our understanding of equine genetic diversity. Full article

Lipizzan is a famous horse breed dating back to 1580 when the original stud of Lipica was established by the Hasburg Archduke Charles II. Currently, the Italian State Stud of Lipizzan Horses (ASCAL) is a conservation nucleus managed through strict mating rules where mitochondrial DNA sequences are used to verify the correct assignment of mares to a historical pedigree maternal lineage. Here, we analyzed the D-loop sequences of Lipizzan horses from the ASCAL in Monterotondo (Rome, Italy) in order to confirm their pedigree assignment to known female founder families. The concurrent investigation of the paternal counterpart based on variation in the male-specific region of the Y chromosome (MSY) showed a prevalence of HT02 (80%), typical of the Neapolitan/Oriental wave. The mtDNA polymorphisms identified shaped nine haplotypes that were unequivocally assigned to each of nine classical mare families of the stud (Africa, Almerina, Argentina, Deflorata, Djebrin, Fistula, Ivanka, Sardinia, Spadiglia), while the Europa and Theodorosta families shared a tenth haplotype. New polymorphisms were identified in a not previously studied region (np 16100–16350). The mtDNA phylogenetic analysis revealed that the Lipizzans of the Monterotondo stud belong to six haplogroups (B, C, G, L, M, Q), out of the 18 recorded for the equine species. This work enabled us to identify and preserve ten haplotypes from the historical maternal lines in a small stud kept in genetic segregation for over 100 years. Full article

New Zealand has the fourth largest feral horse population in the world. The Kaimanawas (KHs) are feral horses descended from various domestic horse breeds released into the Kaimanawa ranges in the 19th and 20th centuries. Over time, the population size has fluctuated dramatically due to hunting, large-scale farming and forestry. Currently, the herd is managed by an annual round-up, limiting the number to 300 individuals to protect the native ecosystem. Here, we genotyped 96 KHs for uniparental markers (mitochondrial DNA, Y-chromosome) and assessed their genetic similarity with respect to other domestic horses. We show that at least six maternal and six paternal lineages contributed unequally to the KH gene pool, and today’s KH population possibly represents two sub-populations. Our results indicate that three horse breeds, namely Welsh ponies, Thoroughbreds and Arabian horses had a major influence in the genetic-makeup of the extant KH population. We show that mitochondrial genetic diversity in KHs (π = 0.00687 ± 0.00355) is closer to that of the Sable Island horses (π = 0.0034 ± 0.00301), and less than other feral horse populations around the world. Our current findings, combined with ongoing genomic research, will provide insight into the population-specific genetic variation and inbreeding among KHs. This will largely advance equine research and improve the management of future breeding programs of these treasured New Zealand horse. Full article