近日，兰州大学Xiang-Peng Yue a等人合作报道了，岔口驿马的遗传多样性、横向步态和高海拔适应性的基因组学见解。该研究于2024年11月19日发表于《遗传学报》。

岔口驿（CKY）马来自青海西藏高原，以其独特的侧向步态和高海拔适应性而闻名，但这些表型的遗传机制尚不清楚。本研究将60个新重测序的有蹄带CKY马基因组，与来自19个马品种的139个公开基因组进行了比较。种群结构分析（混合、主成分分析和邻居联结树）揭示了CKY与其它高原品种（藏马和柴达木马）的亲缘关系。

与其它中国品种相比，CKY马的核苷酸多样性（θπ）和近交系（FROH系数）降低，表明可能存在选择压力。23号染色体上的一个关键区域（Chr23: 22.3-22.6 Mb）与侧步态相关，并且在DMRT3基因中存在一个非常普遍的无义突变（Chr23: 22,391,254 C>A, ser301stop），纯合率为88%，这与CKY马的独特步态密切相关。

此外，选择信号表明，EPAS1基因与高原适应有关，CAT基因与CKY马的高原适应能力有关。这些发现表明，保护遗传多样性对于保持CKY马独特的步态和高海拔适应性至关重要。

附：英文原文

Title: Genomic insights into the genetic diversity, lateral gaits and high-altitude adaptation of Chakouyi (CKY) horses

Author: Xiang-Peng Yue a

Issue&Volume: 2024/11/19

Abstract: Chakouyi (CKY) horses from the QinghaiXizang Plateau are well known for their unique lateral gaits and high-altitude adaptation, but genetic mechanisms underlying these phenotypes remain unclear. This study presents a comparison of 60 newly resequenced genomes of gaited CKY horses with 139 public genomes from 19 horse breeds. Population structure analyses (admixture, PCA, and neighbor-joining tree) reveal a close genetic relationship between CKY and other highland breeds (Tibetan and Chaidamu horses). Compared with other Chinese breeds, CKY horses present reduced nucleotide diversity (θπ) and lower inbreeding (FROH coefficient), suggesting possible selective pressures. A key region on chromosome 23 (Chr23: 22.3-22.6 Mb) is associated with the lateral gaits and harbors a highly prevalent nonsense mutation (Chr 23: 22,391,254 C>A, Ser301STOP) in the DMRT3 gene, with an 88% homozygosity rate, which is strongly correlated with the distinctive gait of CKY horses. Furthermore, selection signals reveal that the EPAS1 gene is related to high-altitude adaptation, and the CAT gene contributes to altitude resilience in CKY horses. These findings suggest that preserving genetic diversity is essential for maintaining the unique gaits and high-altitude adaptations of CKY horses.

DOI: 10.1016/j.jgg.2024.11.008

Source: https://www.sciencedirect.com/science/article/abs/pii/S1673852724003096