Data from: Maternal lineages in native Canadian equine populations and their relationship to the Nordic and Mountain and Moorland pony breeds

A 378-bp section of the mitochondrial displacement loop was used to
estimate genetic diversity in the native Canadian equine populations. The
inclusion of 10 Mountain and Moorland, 3 Nordic pony breeds, 2 feral
populations, and 5 horse breeds were also investigated as they may have
influenced the development (or rejuvenation) of the native Canadian
populations. A total of 281 samples were sequenced, which produced 75
haplotypes derived from 54 informative sites. On further investigation, 36
of these 75 haplotypes were found to be previously unreported. Overall,
total diversity was lowest in the feral Sable Island population with a
haplotype diversity (0.27 ± 0.12), nucleotide diversity (0.0007 ± 0.0004),
and pairwise difference of 0.286 ± 0.317. This is not surprising due to
the geographic isolation of this population. Haplotype diversity was
highest (1.00 ± 0.13) in the New Forest population, pairwise difference
was highest (8.061 ± 4.028) in the Icelandic breed, whereas nucleotide
diversity was highest in the Exmoor breed (0.0209 ± 0.0025). Within the
Canadian populations, haplotype diversity was highest in the Newfoundland
pony (0.96 ± 0.08), whereas pairwise difference and nucleotide diversity
was highest in the Canadian horse (7.090 ± 3.581 and 0.0188 ± 0.0042,
respectively). Three different estimates of genetic distances were used to
examine the phylogenetic relationships amongst these populations. All 3
estimates produced similar topologies. In general, the native Canadian
populations were highly represented in the D clade, with particular
emphasis in the D1 and D2 clades. This is an important factor when
considering the phylogenetic conservation of these Canadian equine
populations.

使用线粒体控制区（mitochondrial displacement loop）的一段378碱基对（bp）序列，对加拿大本土马属种群的遗传多样性进行评估。同时纳入10个山地与沼泽型品种、3个北欧矮马品种、2个野生种群及5个马品种展开研究，因其可能对加拿大本土种群的形成（或复壮）产生过影响。共对281份样本进行测序，得到75种单倍型，均来自54个信息位点。进一步研究发现，这75种单倍型中有36种此前未被报道。总体而言，野生塞布尔岛种群的总多样性最低，其单倍型多样性为0.27±0.12，核苷酸多样性为0.0007±0.0004，核苷酸pairwise差异为0.286±0.317。这一结果并不意外，因其种群具有地理隔离性。单倍型多样性最高的是新森林种群（1.00±0.13），核苷酸pairwise差异最高的是冰岛马品种（8.061±4.028），而核苷酸多样性最高的是埃克斯穆尔马品种（0.0209±0.0025）。在加拿大本土种群中，纽芬兰矮马的单倍型多样性最高（0.96±0.08），加拿大马的核苷酸pairwise差异（7.090±3.581）和核苷酸多样性（0.0188±0.0042）均为最高。采用三种不同的遗传距离估计方法分析种群间的系统发育关系，所有方法均得到相似的拓扑结构。总体而言，加拿大本土种群在D分支中占比极高，尤其集中于D1和D2分支。这一发现对加拿大马属种群的系统发育保护具有重要意义。