中国朝鲜族群体mtDNA编码区3954-4506nt序列多态性

目的 了解中国朝鲜族群体线粒体DNA(mitochondrial DNA,mtDNA)编码区3954-4506nt的序列多态性.方法 采用PCR产物直接测序方法 对198名吉林省延边朝鲜族自治州朝鲜族无关个体进行单倍型分布调查.结果 在198名无关个体中,共分出21种单倍型.遗传变异度为0.5906,偶合概率为0.4124.测序结果 与Anderson序列比较,共检测出19个变异位点,14个与MITOMAP收录的基因突变相同,5个未见收录.结论 mtDNA编码区多态性位点作为mtDNA控制区多态性位点的补充,联合应用可以提高mtDNA的个体识别能力,为mtDNA在中国朝鲜族法医学鉴定提供了基础数据.     

河北汉族群体mtDNA HV1、HV2重叠片段及编码区8430-8673nt序列多态性

目的了解河北汉族群体线粒体DNA(mitochondrial DNA，mtDNA)HV1、HV2区重叠片段及编码区8430-8673nt的序列多态性。方法采用聚合酶链反应-单链构象多态性结合测序方法对100名河北汉族个体进行单倍型分布调查。结果在河北汉族100名健康无关个体中，共分出91种单倍型。遗传变异度为0．9985．耦合概率为0．0115。测序结果与Anderson序列比较，共检测出65个变异位点，44个与MITOMAP收录的基因突变相同，9个与所收录的不同，12个未见收录。结论线粒体DNA在河北汉族群体中有较好的多态性分布，是法医学个人识别和母系亲属认定良好的遗传标记，为mtDNA在河北法医学鉴定提供了基础数据。     

延边地区汉族群体线粒体DNA编码区五个部分序列多态性

目的 了解中国汉族群体线粒体DNA(mitochondrial DNA,mtDNA)5个编码区3954～4506nt、5218～5974nt、7942～8711nt、10296～10653nt及14496～14867nt的序列多态性.方法 采用PCR产物直接测序方法,对200名吉林省延边地区汉族无关个体进行序列多态性变化和单倍型分布调查.结果 在200名无关个体中,共分出110种单体型.遗传变异度为0.9879,偶合概率为0.0171.测序结果与Anderson标准序列比较,共检测出81个变异位点,其中66个与MITOMAP收录的基因突变相同,15个未见收录.结论 mtDNA编码区多态性位点作为mtDNA控制区多态性位点的补充,联合应用可以提高mtDNA的个体识别能力.而且可为中国汉族群体的法医学个人识别、亲权鉴定及民族遗传学研究提供宝贵的基础数据资料.     

那曲地区藏族mtDNA D-环区高变区Ⅰ序列多态性

目的:研究藏族人群线粒体DNA D-环区序列遗传多态性。方法:应用PCR扩增产物直接测序法,对36名藏族无关个体线粒体DNA D-环区高变区Ⅰ(hypervariable regionⅠ,HVR-Ⅰ)进行测序分析。结果:HVR-Ⅰ中404个核苷酸序列与Anderson相应序列比较共发现有51处突变,构成34种单倍型。藏族线粒体DNA的HVR-Ⅰ基因差异度为0.996 1,偶合概率为0.031 6。结论:线粒体DNA D-环区HVR-Ⅰ序列的多态性在人类学、法医学领域具有较高的应用价值。     

西藏昌都藏族mtDNA高变Ⅰ和高变Ⅱ区序列多态性分析

目的 探讨藏族人群线粒体DNA(mitochondrial DNA,mtDNA)控制区的两个高变区(hypervariable region,HVR)Ⅰ、Ⅱ的多态性.方法 采用PCR扩增和末端标记荧光循环测序的方法,对97名西藏昌都地区藏族无关个体进行了序列分析.结果 共观察到111个变异位点,序列变异包括了碱基的转换、颠换、插入、缺失等各种类型.其中,在HVR Ⅰ区(nt16024-nt16365)内观察到68个变异位点,92种单倍型,基因多样性h值为0.9985;在HVRⅡ区(nt73-nt340)内观察到43变异位点,91种单倍型,基因多样性h值为0.9882;随机匹配概率在HVRⅠ和HVRⅡ区P值分别为0.0120和0.0118;联合两个高变区序列,可观察到97种不同的单倍型,随机匹配概率P值为0.0103.结论 昌都藏族与其他群体比较有其独特的mtDNA序列遗传特点,与亚洲其他人种及白人有明显差异.mtDNA序列多态性在群体遗传学调查及法医学个体识别方面有广泛的应用前景.     

西藏僜人mtDNA高变Ⅰ和高变Ⅱ区序列多态性分析

目的 探讨生活在西藏林芝地区僜人群体线粒体DNA(mitochondrial DNA,mtDNA)控制区的两个高变区(hypervariable regions,HVR)Ⅰ、Ⅱ的多态性.方法 采用PCR扩增和末端标记荧光循环测序的方法,对119名僜人无关个体进行了序列分析.结果 共观察到110个变异位点,序列变异包括了碱基的转换、颠换、插入、缺失等各种类型.其中,在HVRI区(nt16024-nt16365)内观察到68个变异位点,119种单体型,基因多样性(h)为0.9916;在HVRⅡ区(nt73-nt340)内观察到42变异位点,113种单体型,基因多样性为0.9907;随机匹配概率(randomly matching probability,RMP)在HVR Ⅰ和HVRⅡ区的P值分别为0.0084和0.0093;联合两个高变区序列,可观察到119种不同的单体型,随机匹配概率P值为0.0084.结论 西藏僜人与其他群体比较有其独特的线粒体DNA序列遗传特点,与中国汉族及亚洲其他群体有明显差异.线粒体DNA序列多态性在群体遗传学调查及法医学个体识别方面有广泛的应用前景.     

广西仫佬族线粒体DNA高变Ⅰ区多态性分析

目的 探讨广西仫佬族人群线粒体DNA高变Ⅰ区的多态性特征,了解仫佬族群体的母系遗传结构。方法 收集91例仫佬族无关男性个体的外周血样本,目标序列用引物L15947和R16488进行PCR扩增,用ABI 3730测序仪正反向测序;计算多态性位点、核苷酸多态性、平均配对差异
数目等多态性指标,以及仫佬族与各民族之间的遗传距离,ME法构建遗传进化树。结果 与修正后的剑桥标准序列（rCRS）比对,91例样本的线粒体高变Ⅰ区序列共界定了74种单倍型,核苷酸多态性为0.0188±0.010,平均核苷酸差异为6.618±3.154;遗传距离显示仫佬族与南方各少数
民族及南方汉族的亲缘关系较近,与北方汉族的亲缘关系较远,进化树中仫佬族与南方少数民族聚为一类。结论 仫佬族在母系遗传上属于典型的南方侗傣族群,可能经历过群体扩张或选择效应;高变Ⅰ区序列具有较高的多态性,可用于法医个体识别、民族起源等方面的研究。     

河北汉族人群四个X染色体短串联重复序列基因座遗传多态性研究

目的调查DXS6800、DXS6797、GATA172D05、DXS9864个基因座在河北汉族人群中的遗传多态性。方法无关个体样本基因组DNA的提取采用酚-氯仿法,家系和腐败降解检材基因组DNA的提取采用Chelex-100法。用PCR和变性聚丙烯酰胺凝胶电泳及DNA序列分析河北汉族150名无关男性及150名无关女性个体DXS6800、DXS6797、GATA172D05、DXS9864个基因座的遗传多态性。结果4个基因座共检测到25个等位基因,男性个体共检出138种单倍型,男性单倍型多样性为0.9986。结论DXS6800、DXS6797、GATA172D05、DXS9864个基因座的多态性数据为X染色体短串联重复序列数据库的建立提供了河北汉族人群的群体遗传学资料。     

应用复合诱导突变分离PCR法检测mtDNA的单核苷酸多态性

目的应用复合诱导突变分离PCR(multiplexed mutagenically separated PCR,MS-PCR)技术、银染分型,建立线粒体DNA(mitochondrial DNA,mtDNA)编码区单核苷酸多态(single nucleotide polymorphism,SNP)分型系统,探讨其应用价值。并调查了成都汉族群体mtDNA编码区4个SNP基因座等位基因频率和单倍型分布情况。方法根据SNP基因座(C12705T、A8701G、G8584A、C10400T)设计两条片段相差4个碱基的等位基因特异性引物和一条公共引物,4个SNP基因座复合扩增,PCR产物经聚丙烯酰胺凝胶电泳、银染显带后确定样本的基因型。结果不同SNP基因座为长度不同的单一谱带,其分型结果与直接测序一致。在成都汉族160名无关个体中,4个SNP基因座C12705T、A8701G、G8584A、C10400T等位基因频率分别为0.3813/0.6187、0.4813/0·5187、0.8250/0.1750、0.4938/0.5062;共检出6种单倍型,单倍型的基因多样性为0.7137。结论建立的MMS-PCR银染分型系统是一种简单、快速、准确、有效的SNP分型方法,对建立mtDNA编码区SNP数据库,研究群体遗传学、进化学和进行法医学个人识别和亲子鉴定有重要意义。     

人线粒体DNA与Y染色体DNA多态性的研究进展

人mtDNA为母系遗传 ,Y DNA为父系遗传 ,且mtDNA分子和Y染色体特异区在减数分裂时均不发生重组 ,这就积累较多的突变 ,记录了人类的进化史 ,因此mtDNA和Y DNA的多态性 ,是探索人类起源、进化和迁移规律有价值的工具。本文介绍了近年来人mtDNA的D环区、V区和Y染色体DNA的双等位基因、多等位基因多态性的研究进展     

中国成都汉族群体线粒体DNA控制区序列多态性研究

目的　检测并分析中国成都汉族群体线粒体 DNA控制区多态性 ,为法医学应用提供基础数据。方法　应用 PCR扩增和直接测序方法检测 10 0个不相关中国成都汉族群体线粒体 DNA控制区中高变区 、 的序列多态性。结果　检测高变区 中 4 0 4个核苷酸和高变区 中 379个核苷酸的序列 ,在 区和 区分别检测到 92和 5 0个变异点 ,与 Anderson标准序列比较 ,共检测到 97种单倍型。偶合概率分别为1.84 %与 1.94 % ,两者合并后为 1.18%。结论　提示线粒体 DNA控制区 DNA序列多态性在法医学领域中具有较高的应用价值。     

Multiplex mutagenically separated polymerase chain reaction assay for rapid detection of human mitochondrial DNA variations in coding area

Recently, it has been recognized that information in the mitochondrial DNA (mtDNA) coding region can provide additional forensic discrimination with respect to the standard typing of the D-loop region, increasing the forensic power of mtDNA testing, which is sometimes rather limited. In the present study, we simultaneously typed ten single nucleotide polymorphisms (SNP) in the coding region by use of mutagenically separated polymerase chain reaction (MS-PCR) in the Chinese Chengdu population. This technique, in which different-size allele-specific primers were used, specifically amplified both alleles of mtDNA in the same reaction. Subsequent gel electrophoresis showed ten of the allelic products of different loci. Using multiplex MS-PCR, 30 primers were added simultaneously into one reaction tube to identify ten SNPs. The mtDNA variations of 160 individuals from the Chinese Chengdu population were examined and classified into 18 haplotypes. The multiplex MS-PCR method is suitable for large-scale screening studies of mtDNA variability because it is both rapid and economical.     

Mitochondrial DNA D-loop in pancreatic cancer: somatic mutations are epiphenomena while the germline 16519 T variant worsens metabolism and outcome

We ascertained the frequency of mitochondrial DNA (mtDNA) D-loop region somatic mutations in pancreatic cancer (PC) and verified whether polymorphisms were linked to diagnosis, prognosis, and PC-associated diabetes mellitus (DM) in 99 PC cases, 42 chronic pancreatitis (CP) cases, 18 pancreatobiliary tract tumors, and 87 healthy control subjects (CSs). Tissue samples were obtained from 19 patients with PC and 5 with CP. The D-loop region was sequenced from all tissue samples and from blood DNA of the same patients and 12 CSs. D-loop somatic mutations were found in 3 PC tissue samples (16%). Four single nucleotide polymorphisms (SNPs; T152C, T16189C, T16519C, A73G), more frequently found in PC than in CS, were analyzed by denaturing high-performance liquid chromatography-restriction fragment length polymorphism using blood DNA as the starting template in all cases. The T allele of 16519 SNP correlated with DM. The survival of patients with PC correlated with tumor stage and grade and with DM at diagnosis. When survival analysis was performed considering only patients with locally advanced disease, the T allele of mtDNA 16519 SNP correlated with shorter life expectancy. mtDNA D-loop somatic mutations, rarely found in PC, cannot be considered causative events for this tumor type and probably are epiphenomena; the mtDNA D-loop 16519 variant, which worsens PC prognosis, seems to be a predisposing genetic factor for DM.     

A collection of 33 novel human mtDNA homoplasmic variants

Mitochondria are involved in cellular energy production via oxidative phosphorylation and this function may be damaged by any mutation in mitochondrial DNA (mtDNA). To identify novel mtDNA mutations, we have developed a program to systematically screen the entire mitochondrial genome in a large number of individuals with clinical and/or morphological features of mitochondrial dysfunction, but still no genetic diagnosis. The sequence-data were obtained with an automated rapid system, which gave us a series of information: in the eleven mitochondrial genomes analyzed we observed the presence of 33 differences from the revised Cambridge Reference Sequence (Andrews et al., 1999), but they were all homoplasmic in the patients' tissues analyzed (skeletal muscle and blood), suggesting that they are unlikely to be primarily pathogenic though they may be co-responsible in the determination of the disease. This work can therefore help complete the already ample mtDNA polymorphism existent database.     

Yield of mtDNA mutation analysis in 2,000 patients

The multiplex polymerase chain reaction–allele specific oligonucleotides (PCR/ASO) dot blot hybridization method was used to detect 44 mitochondrial DNA point mutations in 2,000 patients suspected as having mitochondrial DNA disorders. These point mutations are classified into four categories. Category I consists of primary disease-causing, heteroplasmic point mutations. Homoplasmic nucleotide substitutions that have been reported to be possibly disease associated are in Category II. Homoplasmic nucleotide substitutions that are thought to be benign polymorphism are included in category III. The novel nucleotide substitutions recently discovered in our laboratory by single strand conformation polymorphism analysis are in category IV. Frequencies of these 44 nucleotide substitutions in 2,000 patients and 262 control individuals were studied. The results indicated that analysis of 12 recurrent disease-causing point mutations in category I identified 5.4 % of the patients suspected as having mitochondrial DNA disorders. Since the mitochondrial disorders are a group of complex, heterogeneous, and multisystemic diseases, it is often difficult to confirm clinical diagnosis without molecular studies. Thus, the multiplex PCR/ASO method is an effective approach for initial screening of mtDNA mutations in patients suspected as having mitochondrial DNA disorders. Am. J. Med. Genet. 77:395–400, 1998. © 1998 Wiley-Liss, Inc.     

线粒体多态性检测寡核苷酸芯片的构建

目的构建用于线粒体DNA（mtDNA）D-环控制区（D—LOOP区）多态性多个位点集成检测的寡核苷酸芯片。方法根据GenBank中人mtDNA D—LOOP区序列设计2组引物[普通引物和N,N＇-对羧苄基吲哚三菁（Cy5）标记引物]和55种寡核苷酸探针。将探针固定于醛基修饰载玻片表面,制备mtDNA多态性检测芯片。提取40例健康人外周血标本mtDNA,应用Cy5标记引物不对称PCR扩增mtDNA D—LOOP区片段。取未变性和变性后扩增产物分别与芯片进行杂交,观察二者杂交信号强度差异,并将芯片检测结果与DNA测序结果进行比较。观察等倍稀释的不对称PCR扩增产物的杂交信号强度,检测芯片的灵敏度;将DNA测序结果与探针进行BLAST2比对,找出与PCR扩增产物完全匹配和仅1个碱基不匹配的探针,分析二者在芯片上相应位点杂交信号强度的差异,观察芯片的特异性;以放置6个月后的芯片检测外周血mtDNA,观察杂交信号强度的变化。结果不对称PCR扩增获得的mtDNA D—LOOP区片段（466bp）与预期表达片段大小一致。不对称PCR扩增产物直接杂交和变性后杂交的信号强度无明显差异,40例健康人外周血标本mtDNA的芯片杂交检测结果均与DNA测序结果完全吻合。灵敏度检测结果显示,杂交信号强度随扩增产物稀释程度的增加而减弱,芯片检测靶分子的灵敏度为0．1ng;与DNA测序结果完全匹配的探针174和仅相差1个碱基“C”的探针174c的杂交信号强度具有明显差异;而保存6个月后的芯片杂交信号强度基本保持不变。结论构建的寡核苷酸芯片可满足对mtDNA D—LOOP区多态性进行多个位点快速通量检测的需要,具有较高的灵敏度和特异性,适用于法医鉴定及线粒体疾病的检测。     

Updated comprehensive phylogenetic tree of global human mitochondrial DNA variation

Human mitochondrial DNA is widely used as tool in many fields including evolutionary anthropology and population history, medical genetics, genetic genealogy, and forensic science. Many applications require detailed knowledge about the phylogenetic relationship of mtDNA variants. Although the phylogenetic resolution of global human mtDNA diversity has greatly improved as a result of increasing sequencing efforts of complete mtDNA genomes, an updated overall mtDNA tree is currently not available. In order to facilitate a better use of known mtDNA variation, we have constructed an updated comprehensive phylogeny of global human mtDNA variation, based on both coding- and control region mutations. This complete mtDNA tree includes previously published as well as newly identified haplogroups, is easily navigable, will be continuously and regularly updated in the future, and is online available at http://www.phylotree.org.     

2型糖尿病患者mtDNA变异筛查研究

目的探讨线粒体基因突变与2型糖尿病的关系。方法随机筛查222例散发2型糖尿病患者和191名正常对照，以聚合酶链反应、限制性内切酶片段长度多态性及T-A克隆测序和变性高效液相色谱分析技术验证等方法检测线粒体基因突变。结果糖尿病组线粒体基因（3153—3551nt）突变总的发生率（24．32％）明显高于正常组（7．33％）（P〈0．05）；发现3个尚未见报道的新突变位点：A3209T、T3253G和A3467C，而C3497T则在糖尿病中是首次报道；起病年龄、体重指数、空腹血糖、糖化血红蛋白、高密度脂蛋白和糖尿病肾病等指标是线粒体基因突变的相关因素（P〈0．05）。结论温州地区糖尿病患者存在多种线粒体基因点突变，其在糖尿病的发生发展中起重要作用。