# Genetic Diversity and Population Structure of Fat-Tailed Coarse-Wooled Sheep Breeds Ovis aries from Kazakhstan

## TL;DR

This study explores the genetic diversity of traditional sheep breeds in Kazakhstan, revealing high diversity and ancient lineages that connect domestic sheep to their wild ancestors.

## Contribution

The study identifies high haplotype diversity and ancient maternal lineages in Kazakh sheep breeds, emphasizing their conservation importance.

## Key findings

- High haplotype diversity (Hd = 0.996) and moderate nucleotide diversity were observed in the studied sheep breeds.
- Most genetic variation (92.03%) was found within breeds rather than between them, indicating a long history of mixing.
- The Edilbay breed preserves ancient maternal lineages linked to wild Ovis species and the common ancestor of domestic sheep.

## Abstract

Sheep are one of the most important farm animals in Kazakhstan, where traditional breeds such as Edilbay, Kazakh fat-tailed coarse-wooled, and Gissar are still widely raised. However, little is known about their genetic background. In this study, we examined maternal DNA from these breeds to better understand their diversity and origins. We found that they carry many different genetic types, showing both rich diversity and shared ancestry. Most of the genetic variation was found within breeds rather than between them, which suggests that these sheep have a long history of mixing and exchange. Interestingly, the Edilbay breed appears to preserve ancient maternal lineages that connect modern sheep to their wild relatives. Our findings highlight Kazakhstan as an important region in sheep history and emphasize the need to conserve the genetic diversity of its traditional breeds.

Sheep play a central role in Kazakhstan’s pastoral economy, yet the maternal genetic composition of its traditional breeds remains poorly characterized. We analyzed partial mitochondrial D-loop sequences (848 bp) from 115 individuals of three fat-tailed coarse-wooled breeds (Edilbay, Kazakh fat-tailed coarse-wooled, and Gissar) to assess genetic diversity, population structure, and phylogenetic relationships. Ninety-eight haplotypes were identified, indicating high haplotype diversity (Hd = 0.996 ± 0.002) and moderate nucleotide diversity (π = 0.02624 ± 0.00048). Haplotypes clustered into haplogroups A (57.4%) and B (42.6%), with Edilbay dominating the star-like cluster of haplogroup A, consistent with recent expansion. AMOVA revealed that most variation (92.03%) occurred within populations, with no significant differentiation among breeds. Phylogenetic analyses placed Edilbay close to the most recent common ancestor of fat-tailed domestic sheep and the wild Ovis species, suggesting retention of an ancestral lineage. These findings highlight Kazakhstan as a genetic crossroads in sheep history and underscore the conservation value of its maternal diversity.