# Genome-Wide SNP Analysis Reveals the Unique Genetic Diversity Represented by Fat-Tailed Coarse-Wooled Sheep Breeds of Kazakhstan

## TL;DR

This study uses genetic data to explore the diversity and relationships of three Kazakh sheep breeds, revealing their unique genetic makeup and importance for conservation and breeding.

## Contribution

The study provides the first genome-wide SNP analysis of Kazakh fat-tailed coarse-wooled sheep breeds, highlighting their genetic diversity and distinctiveness.

## Key findings

- The Edilbay breed shows the highest genetic diversity and forms a distinct genetic group.
- Gene flow from Edilbay into other Kazakh populations suggests its role as a genetic source for regional breeds.
- Kazakhstani sheep are closely related to Central Asian breeds but distinct from East Asian and European populations.

## Abstract

Sheep farming is an important part of agriculture in Kazakhstan, especially fat-tailed breeds that are well adapted to the local environment. Namely, Kazakh fat-tailed coarse-wooled, Edilbay, and Gissar sheep breeds are valued for their ability to thrive in harsh pasture conditions, their early maturity, and production of high-quality meat, fat, and wool. Despite their economic and cultural importance, little is known about the genetic background of these animals. In this study, we analyzed genome-wide SNP data from 160 animals representing the three main local breeds to gain insights into their diversity and relationship with other sheep worldwide. Our aim was to explore what makes these breeds unique and how they have developed over time. Understanding their genetics is essential for improving breeding programs, protecting valuable traits, and ensuring the long-term sustainability of sheep farming in Kazakhstan. It also contributes to preserving the country’s agricultural heritage and supporting food security in the region. Our findings show that the Edilbay breed possesses particularly high genetic diversity and forms a distinct group, while some gene flow was also detected among the studied populations. Overall, the native sheep of Kazakhstan represent a significant reservoir of genetic variation in Central Asia, underscoring their importance for conservation and future breeding strategies.

Background: The fat-tailed coarse-wooled sheep breeds exhibit excellent reproductive performance, exceptional adaptability to pasture conditions, and high precocity, contributing to enhanced meat, fat, and wool productivity in sheep breeding. Despite the significant role of these sheep breeds in Kazakhstan’s livestock production, their genetics remain poorly studied. This raises concerns about the potential loss of unique, breed-specific traits that could be important for the future development and resilience of Kazakh stan’s sheep farming sector. This study aimed to analyze genome-wide genotyping SNP data of local fat-tailed coarse-wooled sheep breeds (Kazakh fat-tailed coarse-wooled, Edilbay, and Gissar) to reveal their genetic diversity, breed characteristics, and phylogenetic relationships with worldwide domestic sheep breeds and wild sheep. Methods: The OvineSNP50 Genotyping BeadChip was used to obtain genome-wide SNP genotyping data from 160 fat-tailed coarse-wooled sheep from Kazakhstan. Population structure analysis, principal component analysis, phylogenetic and the maximum likelihood tree analysis were performed in comparison with foreign domestic sheep breeds and wild sheep populations. Results: Kazakh breeds exhibited high genetic diversity, with Edilbay showing the greatest allelic richness. PCA and Admixture revealed clear differentiation among the three breeds: Edilbay and Gissar formed homogeneous clusters, while Kazakh fat-tailed coarse-wooled sheep displayed admixture and substructure. Evidence of gene flow from Edilbay into other Kazakh populations supports its role as a genetic source for regional breeds. Phylogenetic analysis placed Kazakhstani sheep close to other Central Asian breeds, while clearly distinct from East Asian and European populations. Wild sheep (Argali and Urial) formed separate clades, with Kerman wild sheep clustering closer to Urial. Conclusions: Our results highlight the value of genotyping data for studying genetic diversity and population structure. Developing genetic resources for Kazakhstan’s native sheep breeds will help preserve their unique diversity and ensure it remains available for future use in breeding and adaptation efforts.