基于线粒体控制区的鸡不同杂交组合遗传多样性研究

旨在探讨鸡不同杂交组合线粒体控制区（mtDNA D-loop区）的遗传多样性和单倍型特性。选取固始鸡和隐性白羽鸡及其正、反交F1代、藏鸡以及F2代等6个群体共387个个体的mtDNA D-loop区进行测序,分析其遗传规律和单倍型特性,并与不同红色原鸡亚种进行聚类,分析其母系起源。结果显示,6个群体D-loop区全序列大小为1 231 bp,共检测到28个多态位点和1个C碱基缺失,共构成19种单倍型,分为A、B、C和E 4个单倍型群,其中,固始鸡和反交F1代主要为A、C单倍型,固始鸡A、C单倍型比例分别为53.42%和46.58%,反交F1代A、C单倍型比例分别为50.75%和49.25%;隐性白羽鸡、正交F1代和F2代优势单倍型均为E单倍型,占比分别为48.89%、48.84%和50.00%。6个鸡群体单倍型多样度（Hd）在0.496~0.729之间,核苷酸多样度（Pi）在0.003 40~0.005 41之间,Hd值和Pi值最大的均为正交F1代,其次为隐性白羽鸡和F2代,固始鸡和反交F1代群体遗传多样性接近。聚类分析显示,A、B单倍型群与滇南亚种交叉聚为一枝;E单倍型群与印度亚种交叉聚为一枝;C单倍型群与印度亚种、指名亚种、印尼亚种以及滇南亚种聚为一枝。结果提示,mtDNA D-loop区遵循严格的母系遗传,后代的遗传多样性和单倍型比例与其母本基本一致;我国家鸡群体具有多个红色原鸡母系起源,且主要起源于原鸡滇南亚种。     

陆川猪mtDNA D-loop序列遗传多样性分析

本研究测定了陆川猪17个个体mtDNA D-loop高变区序列,共检测到5个单倍型,单倍型多样度和核苷酸多样度分别为0.640和0.0074,表明陆川猪有较高的遗传多样性。结合已报道的中国地方猪种的mtDNA D-loop序列进行分析,结果发现,陆川猪和属于华中型的宁乡猪、大花白猪有很近的遗传关系,但与传统上同属华南型的香猪和滇南小耳猪的遗传关系较远,这与传统的分类方法不一致。     

百宜黑鸡与兴义矮脚鸡线粒体DNA 控制区遗传多样性分析

采用PCR和直接测序的方法测定百宜黑鸡和兴义矮脚鸡线粒体DNA控制区全序列,比较分析两种贵州地方鸡种的遗传变异。结果表明,百宜黑鸡、兴义矮脚鸡mtDNA控制区全序列长均为1231 bp;共发现26个变异位点(不包含种内变异位点),占分析位点总数的2.11%,其中12个转换,14个颠换;百宜黑鸡mtDNA控制区的A、T、G、C碱基含量分别为27.096%、33.628%、13.117%、26.159%,矮脚鸡的A、T、G、C碱基含量分别是A26.916%、T33.409%、G13.387%、C26.288%,t检验结果显示,两种鸡mtDNA控制区的A和T含量差异显著。百宜黑鸡和兴义矮脚鸡的遗传距离是0.0379,根据分子钟计算,二者约在190万年前分歧进化。     

西藏小型猪线粒体DNA控制区的分子遗传学研究

通过扩增102头西藏小型猪以及16头巴马小型猪、17头贵州香猪的线粒体DNA控制区,测序并与国内其他猪种进行比较,研究西藏小型猪的遗传标记以及与其他国内地方猪种的亲缘关系.结果显示,两藏小型猪线粒体DNAD-loop区分3个区域.串联重复序列区处于中间位置,包含有15～29个10 bp的重复片段,分为A、B 2种类型.3'端340 bp,与国内其他猪种的序列相同,比较保守;D-loop 5'端704 bp,共有22个变异位点.由22个变异位点中归纳出25个单倍型,其中有2种主要的单倍型,分别占34.4%和36.6%.根据3个转换位点:305、500、691,将西藏小型猪分成了2组,几乎与串联重复序列所分的A、B 2组类型相对应.与西藏小型猪相比,巴马小型猪和贵州香猪D-loop 5'端变异位点较少,分别只有4种和2种单倍型,串联重复区也只有1个类型.说明西藏小型猪可能有2个母系祖先,并且与我国西南地区的猪种有较近的亲缘关系;不同的串联重复片段类型和5'端的变异位点可以联合组建西藏小型猪的遗传标记.     

猎豹线粒体DNA控制区序列变异研究

18头猎豹线粒体DNA被测序,用来筛选影响猎豹神经衰退疾病的候选基因和候选位点。猎豹的线粒体DNA控制区全长525bp,本研究共发现了28个单核苷酸多态位点,9种单体型。通过构建系统进化树和DNA单体型的降维网的分析,控制区的基因序列根据来源不同明显地分成3个类。本研究为进一步筛选可能影响神经衰退疾病的候选基因和候选位点奠定了基础。     

广西乌鸡线粒体DNA D-loop区序列遗传多样性分析

采用PCR和直接测序的方法测定广西东兰乌鸡线粒体DNA(mt DNA)D-loop第一高变区序列,比较分析东兰乌鸡(片羽、丝羽)的遗传变异。结果表明:在东兰乌鸡mt DNA D-loop区中,共发现27个变异位点,46种单倍型,其变异方式主要是转换和缺失;检测片段的G+C含量(60.59%)明显高于A+T含量(39.41%),具有偏倚性(P0.05);单倍型多样度和核苷酸多样度分别为(0.890±0.020)、(0.01653±0.02483),表明东兰乌鸡的遗传多样性较丰富,其中丝羽乌鸡的变异位点、单倍型数量、单倍型多样度和核苷酸多样度等均比片羽乌鸡高。在NJ系统发生树上,东兰乌鸡分为3大支,说明具有3个血统来源,起源于中国红色原鸡。     

中国地方猪种线粒体基因组遗传多样性及其系统发育分析

为从分子水平上探究中国地方猪种遗传多样性和分类地位,本试验采用生物信息学方法比较了6个类型共22个中国地方猪种的线粒体基因组全序列,分析了其多态性,并构建了6个类型猪种线粒体D-loop区单倍型的网络中介图以及基于线粒体D-loop序列、Cytb基因、完整编码区序列的系统进化树。结果表明,6个类型22个猪种中共检测到了144个多态位点,22种单倍型,说明地方猪种具有丰富的遗传多样性;地方猪线粒体基因组序列中核苷酸变异以转换为主,且Ti/Tv大于转换/颠换比临界值（2.0）,变异位点均符合中性突变。6个类型猪种间遗传距离均较小,且有共享单倍型。系统进化树结果表明,6种类型地方猪种主要聚为两个支系。表明线粒体D-loop序列及Cytb基因均可作为研究种内系统发育、起源进化的分子标记。     

中国部分山羊品种线粒体DNA D-loop序列遗传多样性分析

分析了中国部分本地山羊品种(18个品种200个体)以及在中国饲养的引入品种(4个品种25个体)线粒体DNA控制区(D-loop)的全序列,结合已报道的世界其它地方的山羊(15个品种77个体)以及2只野山羊的线粒体DNA控制区(D-loop)全序列共304个体,研究结果表明:山羊线粒体DNA控制区约为1 212 bp,检测到228个变异位点,203种单倍型,单倍型多样度为0.993±0.001;核苷酸多样度0.018±0.001。中国部分山羊的变异类型主要为类型A和B,而在巴基斯坦山羊中还检测到类型C和D。比较分析结果表明中国山羊遗传多样性和基因交流比中国黄牛品种要高。     

Complete Mitochondrial DNA D-Loop Sequence and Genetic Diversity of Wuzhishan Pig

In order to research the genetic diversity and phylogenies of Wuzhishan pig, 56 complete mtDNA D-Loop were analyzed.55 sequences were amplified by polymerase chain reaction (PCR) and 1 sequence was downloaded from GenBank.The results showed that repetitive sequence "TTATAAAACAC" appeared in the conservative regions of 21 mtDNA D-Loop sequences.13 haplotypes and 14 variable sites were observed in 56 sequences.Haplotype diversity and nucleotide diversity (Hd =0.838 and Pi=0.00334) indicated that Wuzhishan pig had high genetic diversity.Two branches in the phylogenetic tree and Network analysis diagram indicated that there were two maternal origins in Wuzhishan pig.The phylogenetic tree of Wuzhishan pig and other 23 species showed that Wuzhishan pig had close genetic relationship with the pig breeds in the south region of the Yangtze river.     

藏绵羊线粒体DNA遗传多样性研究

本文用ＡｐａＩ,ＡｖａⅡ,ＢａｍＨＩ,ＢｃｌⅡ,ＣｌａＩ,ＥｃｏＲⅤ,ＨｉｎｄⅢ,ＨｐａＩ,ＫｐｎＩ,ＰｓｔＩ,ＰｖｕⅡ,ＸｂａＩ,ＸｈｏＩ等１４种内切酶,分析了１２头藏绵羊ｍｔＤＮＡ的限制性片断长度多态性,共检测了３５个酶切位点,发现ＡｖａⅡ,ＣｌａＩ,ＰｖｕⅡ三种酶切类型具有多态性,根据不同个体的ｍｔＤＮＡ的酶切类型,发现藏绵羊存在三种ｍｔＤＮＡ单倍型,计算ｍｔＤＮＡ多态度π值为０．００１２,     

阿坝藏族羌族自治州若尔盖地区藏猪mtDNA D-Loop的遗传多样性分析

旨在通过获得和对比若尔盖地区藏猪mtDNA D-Loop高变区的部分序列,为该地区藏猪遗传资源的保护与利用提供参考。本试验收集了若尔盖地区9个乡镇共80头藏猪耳组织,以甘南州藏猪mtDNA D-Loop基因序列为模板设计引物,采用PCR扩增测序技术获得了80条核苷酸序列,并采用生物信息学的数据处理方法进行分析。结果表明,若尔盖地区藏猪mtDNA D-Loop高变区（435 bp）的A+T含量（56.46%）明显高于G+C含量（43.54%）,存在碱基偏倚性现象;在80条长度为435 bp的序列中,共检测到14个变异位点,鉴定了17个单倍型,单倍型多样度（Hd）、核苷酸多样度（Pi）和平均核苷酸差异数（k）分别为0.881、0.004 66和2.028,其中Hd、Pi和k在降扎乡藏猪群体中最高,Pi和k在占哇乡藏猪中最低;共享单倍型8个,特有单倍型9个,且若尔盖地区不同藏猪群体间特有单倍型数差异较大,其中,降扎乡藏猪的特有单倍型数量最多,占单倍型总数的17.65%（3/17）;Hap_1和Hap_15单倍型是4个乡镇（降扎乡、益哇乡、热尔乡和冻列乡）群体的共享单倍型,表明这4个乡镇藏猪群体存在两个共同的母系祖先单倍型。若尔盖地区藏猪的平均遗传距离为0.004 66,其中降扎乡和冻列乡藏猪间的遗传距离最大为0.006 90,包座乡和益哇乡藏猪间的遗传距离最小为0.002 16;构建的NJ分子系统进化树将若尔盖地区藏猪分为2支,而加入中国地方家猪、野猪和引种猪后,若尔盖地区藏猪在进化树中比较分散,说明该地区藏猪母源血统遗传复杂,彼此之间基因交流多。本研究进一步证实了若尔盖地区藏猪比西藏林芝、山南、日喀则、甘孜州、阿坝州藏猪的遗传多样性程度高,受到人工选择强度低,应强化对若尔盖地区藏猪遗传资源的保护与利用。     

Study on Genetic Diversity and System Evolution of mtDNA D-Loop Region in Xianglushan Chicken

This study was aimed to analyze the genetic diversity and phylogenetic evolution in Xianglushan chicken.The full-length sequences of mitochondrial DNA D-Loop (mtDNA D-Loop) region of 121 Xianglushan chickens were analyzed by PCR amplification combined with bidirectional sequencing,and the composition,variation and maternal origin of mtDNA D-Loop region were discussed.The results showed that the total length of mtDNA D-Loop region in Xianglushan chicken was 1 231-1 233 bp.The contents of A,T,C and G were 26.62%,33.55%,26.49% and 13.34%,respectively.The content of T was the highest,the content of G was the lowest,and the content of A+T was significantly higher than that of G+C,it indicated that region might have certain base hobbies.Analysis of 121 full-length sequences were found to coexist in 11 haplotypes and 26 mutation sites,of which 2 were single polymorphic information sites,24 were simple information sites,4 bases were inserted and 2 bases were missing.The genetic diversity analysis results showed that the haplotype diversity was 0.814,the nucleotide diversity was 0.00447,the average nucleic acid difference was 5.494,which indicated that the genetic diversity of Xianglushan chicken was relatively rich,the effect of preservation was better,which had a certain breeding space.Tajima's D was 0.39378 and the test results were not significant (P>0.10),in line with neutral mutations.The cluster analysis results showed that Xianglushan chicken and Gallus gallus gathered as one,indicating that Xianglushan chicken originated from Gallus gallus, and there were 4 branches inside the branch,indicating that Xianglushan chicken had many matrilineal origins.The results could provide some reference data for the protection and exploitation of pheasant germplasm resources in Xianglushan chicken.     

Genetic Diversity of Gazella subgutturosa Based on Mitochondrial DNA D-Loop Sequence in Xinjiang Ebinur Lake

To investigate the genetic diversity and genetic data of Gazella subgutturosa from Xinjiang Ebinur lake National Wetland Nature Reserves, the Ebinur lake goose antelope 35 feces samples were analyzed.Using noninvasive DNA technology, the mitochondrial DNA D-Loop 878 bp fragment was successfully amplified.Sequences results for GenBank database BLAST comparison and Clustal W and DNASP software analysis.The results showed that the sequences of the above fragments were successfully amplified, total 55 polymorphic loci were detected, which were not found insert and deficiency.This study found 15 variable sites, including 14 transversion sites and 1 top transposition.The average A, T, C and G contents in D-Loop were 28.03%, 31.57%, 24.84% and 15.56%, respectively.The contents of A+T (59.6%) were higher than G+C (40.4%).In addition, a total of 16 mtDNA haploid type were detected, haploid type polymorphism (h) was 0.886 ±0.037, nucleotide diversity degree (π) was 0.037±0.01528.The results showed that Ebinur lake Gazelle subgutturosa maintained high variation in mitochondrial D-Loop sequences.     

Genetic Diversity and Phylogenetic Relationships of the Complete Mitochondrial Genome in Chinese Indigenous Pig Breeds

In order to explore the genetic diversity and the classification status of the Chinese domestic pigs at the molecular level, the complete mitochondrial DNA (mtDNA) genomic sequences of 22 Chinese indigenous pig breeds from 6 types were downloaded from GenBank for the analysis using the bioinformatics method. The polymorphism of nucleic acid sequences was analyzed,the molecular phylogenetic tree based on D-loop sequences, Cytb gene, complete coding region mtDNA sequences and the Median-Joining network of the mtDNA D-loop haplotypes were constructed for 22 pig breeds from 6 types. The results showed that a total of 144 mutation sites among 22 pig breeds were detected, 22 haplotypes were discovered, which indicated that Chinese indigenous pig breeds had abundant genetic diversity. According to the complete mtDNA genomic sequences analysis, which suggested that the main mutations was transition, the transition/transversion ratio was greater than 2.0 and all mutations were in line with the neutral mutation. Our findings clearly demonstrated that there was a near genetic distance among 6 types, meanwhile, the shared haplotypes were found. The phylogenetic tree showed that Chinese indigenous pigs from 6 types were diverged from two ancestors.The results indicated that mtDNA D-loop and Cytb gene might serve as molecular markers for phylogenesis, origin and evolution.     

固原鸡线粒体DNA控制区全序列测定及分析

固原鸡是宁夏唯一的地方鸡品种资源,具有肉质细嫩、味道鲜美、营养丰富等遗传特性。该试验采用PCR和直接测序的方法测定固原鸡(白羽、麻羽、红羽)线粒体DNA(mtDNA)控制区(D-loop)全序列,结果表明固原鸡3个类群线粒体DNA控制区全序列长度分别为1230bp、1231bp或1232bp。分析种内的遗传变异,3个类群固原鸡共发现6个变异位点,其中4个转换,2个缺失/插入,没有观测到颠换;A、T碱基含量占59.9%~60.0%,G、C碱基含量占40.0%;固原鸡与其它8种禽类的D-loop基因序列同源性的分子进化树聚类结果表明固原鸡不同类群与红色原鸡亲缘关系最近。     

五指山猪背最长肌和半腱肌DNA甲基化检测分析

DNA甲基化作为真核生物基因组重要的表观遗传学修饰,对生物体基因的表达有重要的调控作用。为了研究五指山猪肌肉组织基因组DNA的甲基化程度,试验利用MSAP技术,使用筛选的10对引物扩增,检测五指山猪背最长肌和半腱肌的甲基化程度。结果显示:1月龄、2月龄、4月龄五指山猪背最长肌的平均甲基化率分别是44.78%、41.58%、38.92%;1月龄、2月龄、4月龄五指山猪半腱肌的平均甲基化率分别是41.70%、39.39%、38.81%。研究结果为五指山猪生长发育规律、系统选育及矮小机制等方面的研究提供表观遗传学依据。     

四川黄牛品种线粒体DNA 遗传多样性研究

测定了四川黄牛5个品种的线粒体细胞色素b部分片段（420bp）42个个体以及28个个体线粒体DNA控制区（D-loop）的全序列，结合已报道的中国8个黄牛品种22个个体的线粒体DNA控制区（D-loop）全序列，分析结果表明：四川黄牛的部分Cytb基因片段有5个变异位点，7种单倍型可分为以2个单倍型为主的2大类型；线粒体DNA控制区检测到64个变异位点，28种单倍型，单倍型H1～H23为普通黄牛类型，单倍型H24～H28为瘤牛类型的单倍型。在四川黄牛中，67．86％为普通牛类型，32．14％为瘤牛类型。研究结果表明四川黄牛主要有2类母系来源。     

五指山猪小群体遗传学检测

本研究利用26个微卫星基因座对中国热带农业科学院热带作物品种资源研究所保种场的五指山猪小群体58个样本进行了遗传学检测,用非变性(中性)聚丙烯酰胺凝胶电泳检测微卫星的PCR扩增产物,统计了群体平均基因纯合率、等位基因数,利用等位基因频率计算出各群体的平均遗传杂合度(H)、多态信息含量(PIC).统计结果:全群平均基因纯合率为66.5%;平均多态信息含量、平均观测杂合度为、平均期望杂合度分别为0.807、0.338、0.835;每个位点平均等位基因数为11.92,此结果说明该群体虽然近交程度较高,但仍具有丰富的遗传多样性,遗传变异较大.