Mitochondrial DNA variation and matrilineal structure in blue sheep populations of Helan Mountain, China

Abstract

Mitochondrial DNA (mtDNA) control region (5' hypervariable region, 554 bp) sequences from 71 samples of blue sheep (Pseudois nayaur Hodgson, 1833) collected from six study localities throughout Helan Mountain Nature Reserve in Ningxia province of China were investigated to analyse distribution patterns of genetic variability, elucidate matrilineal structure, and investigate population history. Haplotype diversity (h) among the 71 samples was estimated to be 0.792 ± 0.037, and nucleotide diversity (Å) was relatively low (0.00392 ± 0.00046). A 2 contingency analysis of all mtDNA haplotype frequencies revealed that these haplotypes were distributed in a nonrandom fashion among study localities ( 2 = 86.205, P = 0.092). Additional evidence of matrilineal structure was provided by the finding that a significant amount (9.02%; P < 0.01) of mtDNA variation was partitioned among different localities in the study area. We conclude that blue sheep of Helan Mountain Nature Reserve are structured spatially along matrilines. Pairwise computations of Èst and an AMOVA indicated that some sampling localities are differentiated relative to a random collection of genotypes and reflected differences in the spatial distribution of genetic variation. Isolation-by-distance (IBD) models (Mantel tests) revealed no obvious association between genetic differentiation and geographical distance. These results could be a basis for the development of suitable management strategies for conservation purposes. This work represents the first analysis of blue sheep mitochondrial control region DNA to be performed from a population genetics perspective.Résumé : Nous avons étudié les séquences des régions de contrôle de l'ADN mitochondrial (ADNmt) (région hypervariable 5') dans 71 échantillons de bharals de l'Himalaya (Pseudois nayaur Hodgson, 1833) prélevés dans six localités d'étude réparties dans toute la Réserve naturelle du mont Helan dans la province de Ning-hsia en Chine afin d'analyser les patrons de répartition de la variation génétique, déterminer la structure matrilinéaire et étudier l'histoire de la population. Nous estimons la diversité des haplotypes (h) dans les 71 échantillons à 0,792 ± 0,037 et la diversité des nucléotides (Å) à 0,00392 ± 0,00046, une valeur relativement basse. Une analyse de contingence de 2 de toutes les fréquences des haplotypes de l'ADNmt montre que ces haplotypes ne sont pas répartis de façon aléatoire dans les localités d'étude ( 2 = 86,205, P = 0,092). Une partie significative (9,02 %; P < 0,01) de la variation de l'ADNmt est répartie entre les différ-entes localités de la région d'étude, ce qui appuie aussi l'existence d'une structure matrilinéaire. Nous concluons que les populations de la Réserve naturelle du mont Helan sont structurées dans l'espace d'après des lignées maternelles. Les calculs paire par paire de È st et une AMOVA indiquent que certains points d'échantillonnage se différentient d'une collection aléatoire de génotypes, ce qui reflète les différences de répartition spatiale de la variation gé...

Morphological diversities and ecozones of Ethiopian horse populations

“…The mismatch distribution analyses and the genetic diversity analyses suggest that these breeds must have undergone relatively recent population expansion (Qing et al, 2009). The values of haplotype and nucleotide diversities observed in this study are a little higher than haplotype diversity of 0.792 ± 0.37 and nucleotide diversity of 0.00392 ± 0.00046 observed by Wang et al (2006) from analysis of mtDNA variation and matrilineal structure in blue sheep populations of Helan Mountain, China. However, the values of haplotype diversity are comparable to 0.857 ± 0.137 to 1.000 ± 0.052 reported by Sulaiman, Wu and Zhao (2011).…”

“…A higher variation within than among Nigerian sheep breeds suggests high levels of femalemediated gene flow (Tserenbataa et al, 2004). More so, the results of pair-wise computations and AMOVA indicates that some breeds are differentiated relative to a random collection of genotypes and reflect differences in the spatial distribution of genetic variation (Wang et al, 2006). Similar to these findings, Pariset et al 2011reported that the major mitochondrial variation was distributed within breeds (95.04 percent), while it was lower among regions (0.90 percent) and among breeds within regions (4.06 percent).…”

Taxonomic status of Chinese blue sheep (Pseudois nayaur): new evidence of a distinct subspecies

“…Few individuals can disperse due to both the Tengger Desert and the human activities around the Helan Mountains. This situation may explain why the Helan population is more likely to experience genetic drift and genetic bottleneck, as indicated in a previous study (Wang et al 2006).…”

“…Take the Helan population as an example: the individuals used to be widely distributed across Ningxia. Unfortunately, the population's distribution has been shrinking, so it is now found only in the Helan Mountains (Wang et al 2006) due to increased human-induced activities. Given the relatively low genetic diversity in the Helan population and its isolation from other geographical populations, we argue that a great effort is critically needed for their conservation.…”

Molecular phylogeny and phylogeography of genusPseudois(Bovidae, Cetartiodactyla): New insights into the contrasting phylogeographic structure

“…The entire Cyt b gene sequences were amplified using the primer pairs L14724 and H15915 (Zeng et al., ) and CYF and CYR (Tan et al., ), while the primers D‐LOOP_L2 and D‐LOOP_H2 were used to amplify the 5′ section of the mitochondrial control region (Wang, Cao, Liu, & Fang, ), which includes 554 bp of the hypervariable segment (Eythorsdottir & Tapio, ). Amplification was performed in a total volume of 50 μl containing 50 m m KCl, 10 m m Tris–HCl, 1.5 m m Mg 2+ , 200 μmol of each dNTP, 0.2 μmol of each primer, 1 U Taq DNA polymerase (TaKaRa, China), and approximately 10 ng of genomic DNA.…”