Exploring Genetic Markers: Mitochondrial DNA and Genomic Screening for Biodiversity and Production Traits in Donkeys

SIMPLE SUMMARY: This review article highlights the significance of donkeys as valuable livestock, especially in arid and semi-arid regions, and underscores the importance of implementing breed conservation programs to safeguard genetic diversity among donkey populations. Recent advancements in sequencing and analyzing complete mitochondrial DNA (mtDNA) molecules have revolutionized the evaluation of genetic diversity, with a focus on the mitochondrial D-loop region, which serves as a highly effective genetic marker. Furthermore, extensive research has explored the association between genetic markers at the DNA and RNA levels and production and reproductive traits in donkeys. This article presents a comprehensive review of the evolution of mitochondrial DNA as a tool for assessing biodiversity and genetic markers at the DNA and RNA levels that are linked to productive and reproductive attributes in donkeys. ABSTRACT: Donkeys (Equus asinus) play a pivotal role as essential livestock in arid and semi-arid regions, serving various purposes such as transportation, agriculture, and milk production. Despite their significance, donkey breeding has often been overlooked in comparison to other livestock species, resulting in limited genetic improvement programs. Preserving donkey genetic resources within each country necessitates the establishment of breed conservation programs, focusing on managing genetic diversity among populations. In recent years, significant strides have been made in sequencing and analyzing complete mitochondrial DNA (mtDNA) molecules in donkeys. Notably, numerous studies have honed in on the mitochondrial D-loop region, renowned for its remarkable variability and higher substitution rate within the mtDNA genome, rendering it an effective genetic marker for assessing genetic diversity in donkeys. Furthermore, genetic markers at the RNA/DNA level have emerged as indispensable tools for enhancing production and reproduction traits in donkeys. Traditional animal breeding approaches based solely on phenotypic traits, such as milk yields, weight, and height, are influenced by both genetic and environmental factors. To overcome these challenges, genetic markers, such as polymorphisms, InDel, or entire gene sequences associated with desirable traits in animals, have achieved widespread usage in animal breeding practices. These markers have proven increasingly valuable for facilitating the selection of productive and reproductive traits in donkeys. This comprehensive review examines the cutting-edge research on mitochondrial DNA as a tool for assessing donkey biodiversity. Additionally, it highlights the role of genetic markers at the DNA/RNA level, enabling the informed selection of optimal production and reproductive traits in donkeys, thereby driving advancements in donkey genetic conservation and breeding programs.