利用线粒体 DNA D-环区对阿萨姆野牛（Bos grunniens）的系统发育和群体遗传分析。

Phylogenetic and population genetic analysis of Arunachali Yak (Bos grunniens) using mitochondrial DNA D-loop region.

机构信息

Molecular Genetics Laboratory, ICAR-National Research Centre on Yak, Dirang, Arunachal Pradesh, India.

Animal Genetics and Breeding Laboratory, ICAR-National Research Centre on Pig, Guwahati, Assam, India.

出版信息

Mol Biol Rep. 2024 Nov 6;51(1):1125. doi: 10.1007/s11033-024-10076-9.

DOI:10.1007/s11033-024-10076-9

PMID:39503949

Abstract

BACKGROUND

The Arunachali yak (Bos grunniens) is an important breed native to the northeastern Himalayas of India. Understanding its genetic diversity and evolutionary relationships with other bovine species is crucial for effective conservation and breeding strategies. This study investigates the mitochondrial DNA (mtDNA) D-loop region of Arunachali yak and compares it with other bovines to elucidate these relationships.

METHODS

We collected blood samples from 18 Arunachali yak individuals and isolated genomic DNA. The partial mtDNA D-loop region was amplified using PCR and sequenced. Sequences were compared with those from Bos frontalis, Bos gaurus, Bos indicus, Bubalus bubalis, and Capra hircus available in GenBank. Phylogenetic relationships were assessed through Neighbor-Joining trees and median-joining networks. Genetic diversity indices and neutrality tests were applied to evaluate population genetic characteristics.

RESULTS

Phylogenetic analysis identified three distinct clades, with Arunachali yak clustering closely with Bos indicus, and forming a separate branch from other bovine species. Median-joining networks revealed six haplogroups, with Arunachali yak uniquely representing Hap_3. Genetic diversity analysis showed no polymorphism within Arunachali yak, indicating very low genetic variation in the selected animal samples. AMOVA demonstrated significant genetic differentiation among populations (Fst = 0.30053, P < 0.001), with a substantial portion of variation occurring within populations.

CONCLUSIONS

The Arunachali yak exhibits a close genetic relationship with Bos indicus, reflecting recent divergence. The study underscores the distinct genetic profile of Arunachali yak and highlights its limited genetic variability. These findings enhance our understanding of bovine evolutionary relationships and emphasize the need for targeted conservation measures to preserve the genetic integrity of Arunachali yak.

摘要

背景

阿努拉查利牦牛（Bos grunniens）是一种原产于印度东北部喜马拉雅山脉的重要品种。了解其遗传多样性及其与其他牛种的进化关系对于有效的保护和繁殖策略至关重要。本研究调查了阿努拉查利牦牛的线粒体 DNA（mtDNA）D-环区域，并将其与其他牛种进行比较，以阐明这些关系。

方法

我们从 18 头阿努拉查利牦牛个体中采集血液样本并提取基因组 DNA。使用 PCR 扩增部分 mtDNA D-环区域并进行测序。将序列与 GenBank 中已有的 Bos frontalis、Bos gaurus、Bos indicus、Bubalus bubalis 和 Capra hircus 的序列进行比较。通过邻接法树和中位数连接网络评估系统发育关系。应用遗传多样性指数和中性检验评估种群遗传特征。

结果

系统发育分析确定了三个不同的分支，阿努拉查利牦牛与 Bos indicus 聚类密切，与其他牛种形成单独的分支。中位数连接网络揭示了六个单倍群，阿努拉查利牦牛独特地代表了 Hap_3。遗传多样性分析显示阿努拉查利牦牛内部没有多态性，表明所选动物样本的遗传变异非常低。AMOVA 表明种群间存在显著的遗传分化（Fst=0.30053，P<0.001），大部分变异发生在种群内。