贵州四个山羊品种mtDNA多态性及起源分化

采用15种限制性内切酶,研究贵州省4个山羊(capra sp.)品种共93只个体的线粒体DNA多态性。其中BamHI、HindIII和SalI3种酶的酶切类型存在多态。共检测到18种限制性态型,归结为3种mtDNA单倍型。单倍型I和II在贵州山羊4个品种中分布频率较高,分别为77.42%和21.50%,单倍型III分布频率较低(1.08%);品种间亲缘关系聚类分析表明白山羊和黑山羊亲缘关系最近,其次为黔北麻羊,而与小香羊的亲缘关系最远。

绵羊、山羊和岩羊mtDNA的RFLP及其遗传分化研究

用15种识别6碱基的限制性内切酶ApaⅠ、BamHⅠ、BglⅠ、BglⅡ、ClaⅠ、DraⅠ、EcoRⅠ、EcoRⅤ、HaeⅡ、HindⅢ、KpnⅠ、PvuⅡ、PstⅠ、SacⅠ和SalⅠ对绵羊、山羊和岩羊mtDNA的限制性片断长度多态性进行了比较研究,以探讨其遗传分化关系。

我国北方部分山羊品种mtDNA遗传多样性

我国北方地区有丰富的山羊品种遗传资源。这些遗传资源是人类赖以生存的宝贵基因库之一，是山羊育种不可缺少的重要的遗传材料。因此，对其遗传多样性进行研究具有十分重要的理论和实践意义。然而目前对这些山羊品种的遗传差异，特别是分子遗传的差异却知之甚少。本试验对中国北方地区部分山羊品种和类群的线粒体DNA的限制片段长度多态性进行了研究，以期为我国北方地区山羊品种的起源及遗传分化研究、群体的遗传结构和亲缘关系研究以及品种遗传资源的合理利用和保护研究提供基础资料和科学依据。

中华鲟(Acipenser sinensis)及相关种类的mtDNA控制区串联重复序列及其进化意义

采用PCR技术和DNA测序技术,发现了我国一级珍稀保护动物中华鲟(Acipenser sinensis)线粒体DNA(mtDNA)的控制区(D-loop)存在数目不等的串联重复序列,该重复序列造成了中华鲟广泛的异质性现象。从分子水平进行了不同类型重复序列变化规律的研究,同时还初探了重复序列在我国其它几种鲟鱼类的存在情况,发现在白鲟(Psephurus gladius)、达氏鲟(A. dabryanus)和史氏鲟(A. schrenckii)均存在类似的重复序列结构。

青海湖裸鲤 mtDNA 遗传多样性的初步研究

该文用 BclⅠ、AvaⅠ、BamHⅠ、PstⅠ、KpnⅠ、PvuⅡ 共6种限制性内切核酸酶, 分析了15尾青海湖裸鲤 mtDNA 的限制性片段长度多态性, 共检测出20个酶切位点, 发现 BclⅠ、BamHⅠ和 PvuⅡ 三种酶切类型具有多态性. 根据不同个体 mtDNA 的酶切类型, 青海湖裸鲤存在4种 mtDNA 单倍型, 计算 mtDNA 多态度 π 值为 0.0043, 初步认为青海湖裸鲤在线粒体 DNA 上存在较丰富的群体内变异。

云南文山牛和迪庆牛mtDNA的多态性研究

其它部委、高等院校基金

Pitfalls in the analysis of ancient human mtDNA

The retrieval of DNA from ancient human specimens is not always successful owing to DNA deterioration and contamination although it is vital to provide new insights into the genetic structure of ancient people and to reconstruct the past history. Normally, only short DNA fragments can be retrieved from the ancient specimens. How to identify the authenticity of DNA obtained and to uncover the information it contained are difficult. We employed the ancient mtDNAs reported from Central Asia (including Xinjiang, China) as an example to discern potentially extraneous DNA contamination based on the updated mtDNA phylogeny derived from mtDNA control region, coding region, as well as complete sequence information. Our results demonstrated that many mtDNAs reported are more or less problematic. Starting from a reliable mtDNA phylogeney and combining the available modern data into analysis, one can ascertain the authenticity of the ancient DNA, distinguish the potential errors in a data set, and efficiently decipher the meager information it harbored. The reappraisal of the mtDNAs with the age of more than 2000 years from Central Asia gave support to the suggestion of extensively (pre)historical gene admixture in this region.

中国5种珍稀绢蝶非损伤性取样的mtDNA序列及系统进化

应用非损伤性取样DNA测序技术测定了4种来自云南白马雪山和1种来自新疆天山的5种珍稀绢蝶的线粒体DNA细胞色素b基因部分DNA序列。PAUP3.1.1(简约法)数据分析软件构建该5个种绢蝶的分子系统树显示,爱珂绢蝶(Parnassius acco)和巴裔绢蝶(Parnassius baileyi)的亲缘关系比较接近,阿波罗绢蝶(Parnassius apollo)、珍珠绢蝶(Parnassius orlears)和西猴绢蝶(Parnassius simo)3种绢蝶均为相对独立的一支,其中西猴绢蝶分化较早,与形态学研究结果相吻合。

鲤属鱼类mtDNA控制区（D-环区）序列的变异性分析

采用PCR-测序技术对我国鲤属7个种、亚种和2个品种共62个个体（其中鲤的样品包括采自长江、黄河、松花江三个水系的共4个种群），进行了mtDNA控制区（D-环区）始自3^端共459bp碱基的序列测定，发现其D-环区3^端至中央保守区之间不似其他鱼类和哺乳类是一个单一的高变区，而是在其内部还插有一段长约110bp的保守区，这很可能是鲤属鱼类mtDNA D-环区自身的一个特点。

A phylogeny of Chinese leaf monkeys using mitochondrial ND3-ND4 gene sequences

The phylogeny of Chinese leaf monkeys, especially the snub-nosed monkeys (Rhinopithecus), has not been thoroughly investigated using molecular sequence data, perhaps due to their rarity in the wild and their poor representation in institutional collections. Despite several proposed classifications, systematic relationships of these species remain poorly defined and this has hindered their conservation. To clarify the phylogenetic relationships of the leaf monkey clade in China, we sequenced the mitochondrial ND3, ND4L, ND4, tRNA(Arg), tRNA(His), tRNA(Ser), and tRNA(Leu) genes for Rhinopithecus bieti, R. roxellana, Trachypithecus francoisi, T. f. leucocephalus, and T. phayrei as well as Pygathrix nemaeus and Colobus guereza. We included a rotal of 2252 characters for each individual, excluding gaps in primary sequences. Our interpretation of the results from character- and distance-based phylogenetic analyses suggest that (1) Pygathrix nemaeus is sister to Rhinopithecus rather than to Trachypithecus though it is quite divergent from the former; (2) the Yunnan snub-nosed monkey, Rhinopithecus bieti, represents a valid species; (3) the white-headed leaf monkey is not a distinct species, but instead is a subspecies of Trachypithecus francoisi (T. f. leucocephalus), though it should still be considered a separate evolutionarily significant unit (ESU); and (4) because two individuals of the Phayrei's leaf monkey, T. phayrei, are genetically distinct from one another, a more extensive revision of the taxonomy of this putative species in China is needed. These results, plus ongoing work on the molecular systematics of the entire Asian leaf monkey radiation, can provide a sound basis for identifying the appropriate units of conservation for this endangered group of primates.

Mitochondrial cytochrome b gene sequences of Old World monkeys: With special reference on evolution of Asian colobines

The classification and phylogenetic relationships of the Old World monkeys are still controversial. For Asian colobines, from three to nine genera were recognized by different primatologists. In the present study, we have sequenced a 424 bp mitochondrial tRNA(Thr) gene and cytochrome b gene fragment from Macaca mulatta, Mandrillus sphinx, Mandrillus leucophaeus, Semnopithecus entellus, Trachypithecus vetulus, T. johnii, T. phayrei, T. francoisi, Pygathrix nemaeus, Rhinopithecus roxellanae, R. bieti, R. avunculus, Nasalis larvatus, and Colobus polykomos in order to gain independent information on the classification and phylogenetic relationships of those species. Phylogenetic trees were constructed with parsimony analysis by weighting transversions 5 or 10 fold greater than transitions. Our results support the following conclusions: (1) the Old World monkeys are divided into two subfamilies; (2) that among the colobines, Colobus, the African group, diverged first, and Nasalis and Rhinopithecus form a sister clade to Pygathrix; (3) that there are two clades within leaf monkeys, i.e. 1) S. entellus, T. johnii, and T. vetulus, and 2) T, phayrei and T. francoisi; (4) that Rhinopithecus avunculus, R. roxellanae, and R. bieti are closely related to each other, and they should be placed into the same subgenus; (5) that Rhinopithecus is a distinct genus; and (6) that the ancestors of Asian colobines migrated from Africa to Asia during the late Pliocene or early Pleistocene.

Mitochondrial cytochrome b sequences variation of Protura and molecular systematics of Apterygota

Mitochondrial cytochrome b genes of about 450 bp fragments from 3 proturan species, 5 collembolan species and 2 dipluran species have been sequenced. The number of nucleotide substitutions and Kimura 2-parameter distances have also been calculated, and a series of molecular phylogenetic trees reconstructed by using parsimony and distance methods. The proturan, collembolan and dipluran species have evolved monophyletic groups. The results suggest that Protura and Collembola are sister groups, while Diplura is more or less demonstrating a closer phylogenetic relationship to the pterygotan insects. The phylogeny and their systematic position of protura and other groups are also discussed.

Taxonomic status of the white-head langur (Trachypithecus francoisi leucoscephalus) inferred from allozyme electrophoresis and random amplified polymorphism DNA (RAPD)

Six sample specimens of Trachypithecus francoisi and 3 of T. leucocephalus were analyzed by use of allozyme electrophoresis and random amplified polymorphism DNA (RAPD) in order to clarify the challenged taxonomic status of the white-head langur. Among the 44 loci surveyed, only 1 locus (PGM-2) was found to be polymorphic. Nei's genetic distance was 0.0025. In total, thirty 10-mer arbitrary primers were used for RAPD analysis, of which 22 generated clear bands. Phylogenetic trees were constructed based on genetic distances using neighbor-joining and UPGMA methods. The results show that T. francoisi and T: leucocephalus are not monophyletic. T. francoisi from Guangxi, China and Vietnam could not be clearly distinguished, and they are not divided into 2 clusters. A t-test was performed to evaluate between genetic distances within and between T. leucocephalus and T. francoisi taxa groups. The statistical test shows that the taxa group within T: leucocephalus and T: francoisi does not significantly differ from that between T: leucocephalus and T: francoisi at the 5% level. Our results suggest that the level of genetic differentiation between T, leucocephalus and T. francoisi is relatively low. Recent gene flow might exist between T. francoisi and T. leucocephalus. Combining morphological features, geographical distribution, allozyme data, RAPD data, and mtDNA sequences, we suggest that the white-head langur might be a subspecies of T. francoisi.