Genetic Diversity And Phylogeny Of Gazella Subgutturosa In Mountain Kalamaili Based On Cyt B And D-loop Genes

Goitered gazelle(Gazella subgutturosa) is an important desert ungulates species and mainly lives in the desert and semi-desert of Eurasian areas, it was enlisted as a class II protected species in China. International Union for Conservation of Nature and Natural Resources listed it as vulnerable(VU). In recent decades, due to interference of human activities such as mining development and cross-regional water diversion, Gazella subgutturosa’s habitat was under aggravated destruction and fragmentation, populations continued to decline and many heterogeneous populations appeared. Study on the genetic diversities of Gazella subgutturosa are urgent. We sequenced and analyzed the cytochrome b(Cyt b) gene and D-loop gene of Gazella subgutturosa mtDNA which collected from the Mount Kalamaili Ungulate Nature Reserve. Phylogenetic tree based on the mitochondrial haplotypes using the neighbour-joining method and maximum likelihood method showed two branches, and these two branches have the same topology. They also be divided into two evident branches in the Median-joining network. The degree of genetic differentiation between Clade1 and Clade2 were high(Cyt b:Fst=0.57887; D-loop: Fst=0.60106), and the gene flow values was low,suggested a low degree of genetic exchange(Cyt b: Nm=0.18;D-loop: Nm=0.16). The divergence time between Clade A and Clade B was estimated roughly at 0.08 and 0.086 Mya based on Cyt b and D-loop gene, respectively. The haplotype was relatively high(Cyt b: Hd=0.855;D-loop: Hd=0.964) and the nucleotide diversity was relatively low(Cyt b: π=0.00224;D-loop: π=0.02077). Using Tajima’s D and Fu’s Fs neutral inspection detected the population expansion event based on Cyt b and D-loop sequences respectively and do pairwise mismatch distribution. The test results based on Cyt b gene were very significant, and the pairwise mismatch distribution showed a evident unimodal poisson distribution, indicated that Gazella subgutturosas in a certain period of time may adapt to environmental conditions for survival and development, and the population group happened obvious expansion and sustained growth. But the test results based D-loop gene were not significant, and pairwise mismatch distribution showed a evident multimodal distribution, indicated the population group had no obvious expansion and sustained growth. The difference is because of the different evolution rate of the mtDNA, so we need study the genetic diversities and population genetic structures through nuclear DNA. The phylogenetic trees indicated Gazella subgutturosa, Gazella bennettii, Gazella cuvieri and Gazella leptoceros are earlier species that separated from Gazella, and Gazella bennettii is the nearest species to Gazella subgutturosa. The mtDNA results of Gazella subgutturosa can guide the reserve make scientific protection measures and provide foundation to protect the genetic resources of Gazella subgutturosa.