安徽汉族群体mtDNA高变区I序列多态性分析

以Anderson标准序列作为对照,用GeneDOC软件确定42个安徽汉族无关个体的mtDNA高变区I序列在线粒体基因组中的位置,通过序列比对软件clustalX分析安徽汉族群体mt DNA高变区I序列多态性,共检测到38种单倍型和57个变异位点.在mtDNA高变区I序列中14个bp的高变结构域中,安徽汉人16183位点变异率高达38%,在16187位点的变异率为4.8%.同时发现,安徽汉人与成都汉人在mtDNA高变区I 16183和16189位点的变异率接近,明显高于广东汉人.     

FMMU白化豚鼠线粒体DNA RFLP分析研究

目的研究FMMU白化豚鼠的mtDNA,并与花色豚鼠mtDNA进行多态性分析比较,以确定其独特的生物学特性是否与mtDNA相关。方法用碱变性法提取FMMU白化豚鼠以及花色豚鼠的mtDNA,并用AvaⅠ、BalⅠ等12种限制性内切酶进行酶切和限制性片段长度多态性分析。结果与结论FMMU白化豚鼠mtDNA和花色豚鼠mtDNA的相对分子质量相同,约为16.7×103;FMMU白化豚鼠与花色豚鼠两品系的mtDNA经AvaⅠ、BalⅠ等内切酶酶切后有3-8个酶切位点,酶切图谱完全相同,经RFLP分析FMMU白化豚鼠与花色豚鼠的mtDNA之间缺乏多态性。本实验没有发现FMMU白化豚鼠的独特的生物学特性与mtDNA相关。     

中国内蒙古鄂伦春族线粒体DNA高变区Ⅰ和高变区Ⅱ遗传多态性

收集50份鄂伦春族无关人群外周血样本, 用ABI PRISM377测序仪对其mtDNA HVRⅠ和HVRⅡ进行测序, 计算多态性位点数、单倍型数目、单倍型频率、平均核苷酸差异数目等多态性指标; 结合已发表的其他民族mtDNA遗传资料, 根据Nei法计算鄂伦春族与各群体之间的遗传距离, 进行聚类分析, 绘制系统发生树。鄂伦春族群体mtDNA两个高变区与CRS序列比对, 分别发现52和24个多态性位点, 分别界定了38和27种单倍型, 单倍型多态性分别为0.964±0.018和0.929±0.019; 平均核苷酸差异分别为7.379和2.408; 用HVRⅠ序列多态性数据计算Fst和dA两种遗传距离, 相关系数r为0.993(P<0.01); 基于HVRⅠ序列的系统树显示鄂伦春族与中国台湾、南方汉族和中国香港人群遗传距离较近, 与北方汉族、蒙古族及其国外人群遗传距离相对较远。我国鄂伦春族人群mtDNA具有相对独特的遗传特征, 其遗传多态性和个体识别力较高, 可用于民族起源、迁徙、法医学个体识别等领域研究。     

马鹿线粒体DNA研究新进展

线粒体DNA作为理想的分子遗传标记被广泛应用于马鹿进化生物学、种群遗传学和保护生物学的研究.该文阐述了mtDNA在马鹿中的研究进展,重点介绍马鹿mtDNA序列的研究概况及其多态性在马鹿物种识别、起源和进化、地理分化、遗传多样性和保护管理等方面的应用情况.     

中国三种实验用小型猪mtDNA D-l00P多态性分析

分析中国三种实验用小型猪线粒体DNA(mtDNA)D-loop的多态性,建立各品种品系猪的遗传标记,为各品种品系猪的鉴别提供依据.应用PCR对西双版纳近交系小耳猪、广西巴马小型猪、贵州小型香猪和长白猪血液总DNA样品中mtDNA D-loop进行扩增,用23种限制性内切酶消化,观察其酶切多态.PCR扩增其mtDNA D-lcop 5′端227 bp高变区域,应用PCR-SSCP和PCR直接测序分析,观察其单链构象多态和序列多态.结果显示:3种小型猪之间未见酶切长度多态、单链构象多态和序列多态;与长白猪之间表现出单链构象多态和序列多态.本研究认为:3种实验用小型猪之间mtDNA多态性贫乏,证明其在母系起源和进化上的一致性,亲源关系很近,应用PCR-RFLP、PCR-SSCP和PCR直接测序分析,尚不能作为3种实验用小型猪品种品系鉴定的依据,但与长白猪等欧系猪比较有一定差异.     

新疆两个民族人群线粒体DNA V区缺失多态性

目的：调查中国新疆塔吉克族和柯尔克孜族人群线粒体DNA COⅡ／tRNA^Lye基因间小非编码V区串联重复序列9-bp缺失频率。方法：应用PCR及DNA序列分析技术。结果：研究发现,在塔吉克族及柯尔克孜族样本中只发现标准型和缺失型两种多态性,70例柯尔克孜族人群中有2例（2．86％）mtDNA 9bp缺失;70例塔吉克族人群中有1例（1．43％）mtDNA 9-bp缺失。结论：研究结果表明中国新疆塔吉克族和柯尔克孜族人群中存在很少的mtDNA 9bp缺失多态性,与其他民族或人种有一定差异。     

中国三种实验用小型猪mtDNA D—loop多态性分析

分析中国三种实验用小型猪线粒体DNA（mtDNA)D-loop的多态性,建立各品种系猪的遗传标记,为各品种品系猪的鉴别提供依据,应用PCR对西双版纳近交系小耳猪,广西巴马小型猪,贵州小型香猪和长白猪血液总DNA样品中mtDNA D-loop进行扩增,用23种限制性内切酶消化,观察其酶切多态,PCR扩增其mtDNA D－loop5‘端227bp高变区域,应用PCR－SSCP和PCR直接测序分析,观察其单链构象多态和序列多态结果显示,3种小型猪之间未见酶切长度多态,单链构象多态和序列多态,与长白猪之间表现出单链的构象多态和序列多态,本研究认为：3种实验用小型猪之间mtDNA多态性贫乏,证明其在母系起源和进化上的一致性,亲源关系很近,应用PCR－PFLP,PCR－SSCP和PCR直接测序分析,尚不能作为3种实验用小型猪品种品系鉴定的依据,但与长白猪等欧系猪比较有一定差异。     

荧光-构象敏感凝胶电泳技术筛查上海市郊区野生小家鼠线粒体编码区SNP位点

利用通用引物荧光PCR方案, 应用荧光-构象敏感凝胶电泳(fluorescence-based conformation sensitive gel elec-trophoresis, F-CSGE)和DNA直接测序分型技术, 对上海地区64只野生小家鼠线粒体DNA(mtDNA)编码区进行序列分析, 在上海市郊区野生小家鼠群体中初步检测mtDNA编码区SNP, 以发现合适的遗传位标用于野生小家鼠遗传多态性分析。结果发现: F-CSGE所有存在SNP突变的峰图中同源双链和异源双链峰电泳泳动距离差异均较为明显, 在检测未知SNP中无假阳性出现, 检测效率高。F-CSGE检出野生小鼠mtDNA编码区SNP 24个, 其中新发现SNP为16个。结果表明, F-CSGE可用于mtDNA编码区SNP检测, 新发现的SNP可作为遗传位标用以研究整个上海地区野生小家鼠的遗传结构和遗传多态性。     

中国人线粒体DNA的八种限制酶图及其电镜结构

尽管Anderson等人(1981)已测定了人mtDNA的全部序列,但还不能全面地反映整个人类mtDNA核苷酸序列的情况。因此,在具有代表特征的中国人mtDNA序列被测定之前,为了开展对中国人mtDNA的遗传学研究,笔者构建了中国人mtDNA的8种限制酶图。并通过电镜技术对mtDNA进行了研究,发现了一种周长为2μm的小环状DNA,推测它可能在核DNA和mtDNA之间的信息传递或衰老发生中起到某些作用。     

辽东湾斑海豹(Phoca largha)线粒体D-loop区异质型研究初探

采用PCR技术和DNA克隆测序技术,随机测定了3头斑海豹mtDNA控制区(D-loop区)csn-3上、下游1000bp左右的序列,每头斑海豹任选14个克隆菌斑进行测序,结果所得序列均无重复,得到42个单倍型.结合GenBank已发表的斑海豹mtDNA控制区序列(Phoca largha,AM181031),通过Clusta1X1.83、MEGA3.1和FastPCRv3.6等生物信息学软件进行序列比对,发现我国珍稀保护动物斑海豹个体内线粒体DNA(mtDNA)的控制区CSB-3之后存在异质型现象,且存在数目不等的串联重复序列.从分子水平进行了不同类型重复序列变化规律的研究,初探了mtDNA控制区异质型在斑海豹中的存在情况.     

耐力运动员及普通人群线粒体DNA调控区遗传多态性分析

目的：通过ＰＣＲ技术对优秀耐力项目运动员以及普通个体的ｍｔＤＮＡ调控区遗传多态性进行分析,以期发现与运动能力相关联的基因标记。方法：以单根毛发为检材,运用ＰＣＲ技术分析中国优秀耐力性项目运动员（ｎ＝６７）,一般水平运动员（ｎ＝３３）以及普通人群（ｎ＝２０）的线粒体ＤＮＡ调控区（Ｄ－Ｌｏｏｐ）的ＲＦＬＰ。结果：优秀耐力性项目运动员线粒体特定区域ＲＦＬＰ分布与普通人群至显著性差异。结论：一些在优秀运动     

Polymorphism of human mitochondrial DNA

To date, a large data set on the mitochondrial DNA (mtDNA) sequence variation in human populations has been accumulated. The use of direct sequencing of the main noncoding region of mtDNA along with the RFLP analysis provide performance of complex analysis of mtDNA polymorphism in human populations. This approach proved to be effective for obtaining molecular genetic portraits of the world populations, as well as for the elucidation of the human evolutionary history and past migrations.     

Polymorphism of Human Mitochondrial DNA

To date, a large data set on the mitochondrial DNA (mtDNA) sequence variation in human populations has been accumulated. The use of direct sequencing of the main noncoding region of mtDNA along with the RFLP analysis provide performance of complex analysis of mtDNA polymorphism in human populations. This approach proved to be effective for obtaining molecular genetic portraits of the world populations, as well as for the elucidation of the human evolutionary history and past migrations.     

线粒体DNA U4b单倍群:中国塔吉克族高原原发性高血压的遗传易感因素

目的:探讨线粒体DNA变异与中国塔吉克族高原原发性高血压的关系.方法:在中国塔吉克族人群中,收集了 53例高原原发性高血压病例和46例正常对照.通过PCR扩增线粒体DNA片段,经测序拼接获得线粒体全基因组,与剑桥序列比对以筛选线粒体DNA变异,分析在病例组与对照组中的分布差异,采用生物信息学工具预测阳性相关变异的功能....     

SSCP analysis of pig mitochondrial DNA D-loop region polymorphism

The sequence polymorphism that occurs in the mitochondrial DNA (mtDNA) displacement (D)-loop region is useful as a cytoplasmic DNA marker. We cloned the mtDNA D-loop regions of five breeds of pig by polymerase chain reaction (PCR) and determined their sequences. The sequence diversities in D-loop regions among five breeds of pig were located in the starting area of heavy-strand replication. From these sequences, we designed primers for PCR-mediated single-strand conformation polymorphism (PCR-SSCP) analysis that amplified the most polymorphic 227 bp fragment of the D-loop region. The results of PCR-SSCP analysis clearly showed that four types of polymorphism (A to D) are found in Landrace (A), Large White (A, B), Duroc (A), Göttingen miniature pig (B) and Meishan (C, D). The same polymorphisms were also detected from each porcine embryo by this method. Our results show that PCR-SSCP analysis is useful in detecting polymorphisms in the D-loop region of pigs and pig embryos.     

STR polymorphism of mtDNA D-loop in rhesus macaques of Bangladesh

Molecular variation of mitochondrial DNA (mtDNA) was investigated for rhesus macaques (Macaca mulatta) of Bangladesh. A partial sequence (583–599 bp) of mtDNA containing the second variable region of the D-loop was compared for 39 individuals from five localities in the country. A total of seven haplotypes were detected with substitutional or insertion/deletion mutations. They contained a unique polymorphism of pentanucleotide STRs (short tandem repeats). There were at least four different length types, from two to five repeats of the unit nucleotide. One site of substitution and one site of single nucleotide insertion/deletion were also involved in the polymorphism. The mutation hot spots of the STR polymorphism were located between the first and second conserved sequence blocks (CSB1 and CSB2), as observed previously in some other mammals. The geographical distribution of the STR polymorphism revealed local differences; the northeastern population was polymorphic with three STR haplotypes, but other local populations were simply monomorphic with a single STR haplotype. Molecular phylogenetic analysis with reported sequences from outside Bangladesh indicated a low substitution diversity of mtDNA in Bangladesh. Clustering results suggested a close relationship to India and divergence from Laos and China.     

Phylogenetic relationships within Hevea brasiliensis as deduced from a polymorphic mitochondrial DNA region

We have cloned a 4.5-kb mtDNA fragment showing a high RFLP polymorphism between various Hevea genotypes. Subcloning and sequencing of a 1.4-kb segment of this clone allowed us to design PCR amplification primers to isolate homologous mtDNA segments of about 0.9 kb from 23 representative genotypes of Hevea. Complete sequences from 4 genotypes showed between 6.7% and 20.2% of nucleotide diversity, suggesting the presence of a hypervariable, or hotspot, region. A sequence of 345 nucleotides within this region was determined for the 23 genotypes. The phylogenetic relationships inferred from the sequence comparison are in general agreement with the results obtained from mtDNA RFLP analysis, indicating that this polymorphic mtDNA region is a useful molecular marker for phylogenetic analysis within Hevea.     

A high frequency of mtDNA polymorphisms in HeLa cell sublines

The complete mtDNA sequences from the uncloned "founder" HeLa cells and from five sublines have been determined. These sequences all carry a common "core" of 38 single basepair alterations relative to the revised Cambridge Reference Sequence (CRS). The HeLa mitochondrial genome is of African descent and it is a member of the African L3 haplogroup. The sequence of the HeLa mtDNA resolves the uncertainty surrounding the mosaic composition of the original CRS for human mtDNA. Most importantly, we detected a total of eight polymorphisms that have arisen in the mtDNA coding region of different HeLa sublines. These observations suggest that HeLa mtDNA has a high rate of sequence divergence, relative to the phylogenetically-derived divergence rate for mtDNAs in the human population, which results from a relaxation of negative selection against the fixation of deleterious mutations. Furthermore, this high frequency of polymorphisms in HeLa mtDNA may reflect a process similar to the accumulation of somatic mtDNA mutations in human cancers. Preliminary analysis of single-cell derived subclone lines revealed the occurrence of another polymorphism and provided evidence for a large number of mtDNA segregation units.     

Mitochondrial DNA analysis of Sporothrix schenckii clinical isolates from China

Mitochondrial DNA (mtDNA) types based on restriction fragment length polymorphism (RFLP) patterns with HaeIII were investigated in clinical isolates of Sporothrix schenckii in China. In addition to 23 mtDNA types (Types 1-23) so far reported, a new mtDNA type (Type 24) was found in this study. Type 24 was divided into two subtypes, Subtype 24A and 24B based on RFLP with EcoRV. Sixty-seven isolates in China consisted of 58 isolates of Type 4, 5 of Type 6, 1 of Type 5, 1 of Type 20 and 2 of Type 24. Based on the phylogeny of the mtDNA types (Types 1-24) constructed by estimating sequence divergences of mtDNA, mtDNA types clustered into two groups: Group A (Types 1-3, Type 11, Types 14-19 and Types 22-23) and Group B (Types 4-10, Types 12-13, Types 20-21 and Type 24). These results suggest that most S. schenckii isolates in China belong to Group B.