五指山猪线粒体控制区序列分析及遗传多样性研究

为了研究五指山猪遗传多样性和系统地位,本研究采用PCR产物直接测序法得到55条五指山猪线粒体控制区(mtDNA D-Loop)全序列,并结合GenBank中发表的1条五指山猪mtDNA D-Loop全序列进行结构分析、遗传多样性研究及系统发育分析。结果发现,56条序列中出现21次保守区变异,即"TTATAAAACAC"序列重复,共定义13个单倍型,发现14个变异位点,单倍型多样度(Hd)和核苷酸多样度(Pi)分别为0.838和0.00334,表明五指山猪遗传多样性较丰富。五指山猪线粒体控制区序列构建的系统发育树和Network网络分析呈现两大分支,推测有两个母系起源,且与GenBank中其他23个猪种的聚类结果表明,五指山猪与长江流域以南地区的猪种有着较近的亲缘关系。     

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.     

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。     

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.     

建昌马mtDNA D-loop区遗传多样性及系统进化分析

试验旨在以线粒体DNA(mitochondrial DNA,mtDNA)为切入点,研究建昌马的母系遗传多样性与系统进化。从建昌马(n=39)血液中提取基因组DNA,用PCR方法扩增mtDNA D-loop区并直接测序,分析其高变区247 bp序列信息,统计mtDNA D-loop区的单倍型及变异位点,计算单倍型多样性(haplotype diversity,Hd)、核苷酸多样性(nucleotide diversity,Pi)和平均核苷酸变异数(average number of nucleotide differences,K)。构建包括建昌马在内的19个品种马的NJ系统进化树,计算各品种间的遗传距离。结果显示,试验获得了清晰的PCR扩增产物,并通过直接测序方法获得了约1200 bp的序列。39匹建昌马mtDNA D-loop区247 bp序列(其中1个样品缺失1 bp)的AT碱基含量为61.45%,属AT碱基对富集区,检测到33个多态性位点,共显示26种单倍型,其中4种为共享单倍型,且Hap7和Hap1为优势单倍型,单倍型多样性为0.947,核苷酸多样性为0.02399,平均核苷酸变异数为5.901,显示丰富的母系遗传多样性;NJ系统进化树显示,建昌马分布在A、C、D、E、F、G共6个支系中,约50%的样品分布在A支系,显示出复杂的母系起源;建昌马与关中马的遗传距离最小(0.021),其次是三河马、文山马、韩国车巨马(0.024),与韩国济州岛马遗传距离最大(0.032)。本研究结果表明,建昌马的mtDNA D-loop高变区遗传多样性丰富,具有多个母系起源,且A支系占有明显优势,与关中马、文山马可能有共同的母系起源。     

Analyses of Genetic Diversity and Phylogeny of mtDNA D-loop from Yak in Karakoram-Pamir Area

This experiment was conducted to clarify the genetic diversity,genetic differentiation and phylogenetic status of yak in Karakoram-Pamir area.The mtDNA D-loop region sequence was selected as a molecular marker,and the sequence and genetic diversity of the mtDNA D-loop region of yak in Karakoram-Pamir area were analyzed by PCR direct sequencing and bioinformatics methods.The yak sequence in GenBank was used.The maximum likelihood method was used to construct the phylogenetic tree and the intermediary network relationship.The results showed that the mtDNA D-loop sequence of yak in Karakoram-Pamir area was rich in A and T bases,with AT content of 61.2%,and there were 63 polymorphic loci,accounting for 7.04% of the total number of nucleotides.The results indicated that A and T bases were rich in the mtDNA D-loop sequences at 61.2%.There were 63 mutation sites,accounting for 7.04% of all nucleotides,The average haplotype diversity (Hd) was 0.806,the average nucleotide diversity (π) was 0.01528,and the average nucleotide difference (K) was 13.509,indicating that the yak was rich in genetic diversity in Karakoram-Pamir area;Through phylogenetic analysis,there were two branches in yak in China,forming two branches and six small clades.The yak in Karakoram-Pamir area involved in this study had two different maternal origins.Additionally,yak in the Karakoram-Pamir area was less shared with other breeds of yak haplotypes.In the branch C,the yak group in the Karakoram-Pamir area accounts for a large proportion and was shared with wild yak.The yak population in Karakoram-Pamir area had a unique genetic background,which might be the result of early domestication of wild yaks.It was suggested to increase the identification of yak breeds and the formulation of breed standards in this area,and strengthen the protection of yak genetic resources in this area.According to the current situation of the population,wild blood yaks were introduced for purification and rejuvenation to prevent breed degeneration and decrease of genetic diversity.The introduction of foreign yak breeds and disorderly hybridization were reduced to ensure the characteristics of this breed of high-quality yak breed resources.     

深县猪mtDNA CytB基因的遗传多样性与母系起源研究

为探讨深县猪群体内的遗传多样性及母系起源分化,采用PCR直接测序法测定了40头深县猪的mtDNA CytB基因长1 140 bp片段的全序列,并结合GenBank已公布的15个猪种mtDNA CytB基因全序列,采用邻接法构建深县猪、部分其他地方猪种和引进猪种的系统发育树。结果显示,在1 140 bp长的序列中A、T、G、C的含量分别为25.93%、31.72%、28.90%及13.45%,其中A+T的含量(57.65%)高于G+C的含量(42.35%);共发现2个变异位点,无插入和缺失突变,全部为转换位点,其中简约信息位点2个,未发现单一信息位点。40条序列共定义了3种单倍型,单倍型多样性(HD)为0.312,核苷酸多样性(Pi)为0.00026,平均核苷酸差异数(K)为0.327。在深县猪mtDNA CytB基因全序列NJ进化树中,三种单倍型聚为同一分支,母系来源单一,与莱芜猪、大蒲莲猪等山东品种遗传距离较近。结果表明,深县猪群体内遗传多样性比较贫乏,与山东地区的华北型黑猪种群有更近的亲缘关系。     

利用DNA条形码对海南特种野猪的鉴定研究

试验旨在探讨以猪的细胞色素氧化酶Ⅰ（cytochrome C oxidase subunitⅠ,COXⅠ）基因的特定区段作为DNA条形码识别海南特种野猪与其他品种的可行性和有效性。以海南特种野猪、海南野猪、屯昌猪、五指山猪及长白猪为研究对象,测定其COXⅠ基因,同时在NCBI中下载已发表的具有地方代表性的13个猪品种的COXⅠ基因序列,分析海南特种野猪与其他品种的遗传多样性、遗传距离,并构建系统进化树。结果发现,猪COXⅠ基因序列长1 419 bp,5个猪品种45个个体COXⅠ基因共检测到67个变异位点,占分析位点的4.7%,其中简约信息位点22个;5个猪品种的种内遗传距离为0.001~0.019,其中海南特种野猪的种内遗传最大,为0.019;5个猪品种的种间遗传距离为0.009~0.123,其中海南特种野猪与长白猪的遗传距离最大,为0.123;海南特种野猪杂交情况比较明显,与海南本地品种五指山猪、屯昌猪和海南野猪都有聚类,与武夷黑猪、三都黑猪、陆川猪位于一个分支,另一部分与大花白猪位于一个分支,与长白猪没有聚类。本试验结果为海南特种野猪的进一步选育提供了参考依据。     

The Genetic Diversity and Phylogenetic Relationships of Five Guangxi Pig Breeds and Three Exotic Pig Breeds by Analysis of mtDNA D-loop Sequences

In order to compare the genetic diversity and phylogenetic relationships between Guangxi pig breeds and three exotic pig breeds,one pair of primers was used to amplify 85 mtDNA D-loop sequences of five Guangxi pig breeds (Bama Xiang pig,Dongshan pig,Guizhong spotted pig,Luchuan pig,Huanjiang Xiang pig),and we downloaded 45 mtDNA D-loop sequences of three exotic pig breeds (Duroc,Yorkshire,Landrace) from GenBank.Then the haplotype,genetic diversity and phylogenetics analysis were carried out.The results showed that 38 haplotypes were identified in 130 sequences,and the mean distances among Guangxi pig breeds were smaller than that among Duroc,Landrace and Guangxi pig breeds.The NJ phylogenetic tree classified all samples into two clusters.One contained all of Guangxi pig breeds and partial Yorkshire,the other was composed wholly of exotic pig breeds,which mean there were two distinct maternal origins.In the cluster of Guangxi pig breeds,Luchuan pig were clustered,and the others were rather dispersive.It indicated that Luchuan pig had simple maternal bloods,and the other breeds had complex maternal bloods,and they had gene flow with each other.The maternal pig resources in Guangxi were not affected by the introduction of exotic pig breeds,and they were still suitable for use as a female parent in their development and utilization.     

民猪FoxN1基因的克隆及生物信息学分析

试验旨在对民猪FoxN1基因的结构和功能进行初步探索。利用常规PCR技术对民猪FoxN1基因进行克隆,利用生物信息学手段对所获得FoxN1基因完整编码区序列进行分析,对民猪和大白猪的FoxN1基因序列进行比对,并构建分子进化树。结果显示,民猪FoxN1基因完整编码区长1 941 bp,编码646个氨基酸,分子质量为68.64 ku,理论等电点为5.81。FoxN1蛋白位于细胞核内,不存在信号肽,不是分泌性蛋白,不存在跨膜区,在第269-347氨基酸处有1个叉头结构域,该蛋白在不同的物种间有高度的保守性。克隆发现了3种转录剪切变异体,与变异体1相比,变异体2在第124-387核苷酸位置处发生缺失,变异体3在581-582处发生GCA插入。民猪与大白猪的FoxN1基因序列相比,存在4个突变位点,其中3个是同义突变,1个是错义突变,导致第108位的氨基酸发生了改变。由分子进化树得知,民猪与偶蹄目动物亲缘关系较近。上述结果表明FoxN1基因结构复杂,对其生物信息特性的探究将为进一步揭示民猪FoxN1基因的功能提供依据。     

A Genetic Diversity Analysis of Mitochondrial DNA D-loop Region in Four High Quality Chicken Breeds

This study was conducted to elucidate the genetic diversity of mitochondrial DNA (mtDNA) D-loop region in Qingyuan partridge chicken group 1,Qingyuan partridge chicken group 2,Yangshan chicken and Qingyuan Yellow feather black-bone chicken.The specific primers were designed according to mtDNA D-loop region of Gullus gullus spadiceus (accession No.:NC_007235.1) in GenBank.The sequence was analyzed after PCR amplification and sequencing,and the haplotype number,polymorphism number,haplotype diversity,nucleotide diversity and nucleotide mean difference were counted.The evolution divergence among breeds was calculated by Mega 5.10 software,and the phylogenetic tree was constructed.The results showed that the length of mtDNA D-loop region in four high quality chicken breeds was 591 bp,and 549 bp were used for subsequent analysis.The content of A,T,C and G were 27.2% to 27.3%,30.1% to 30.4%,29.5% to 29.8% and 12.8% to 12.9%,respectively,and the average content of G+C was 42.5%.There were 92 polymorphic sites which contained 14 singleton variable sites and 78 parsimony informative sites,and the percentage of transitions and transversions were 89.13% (82/92) and 10.87% (10/92),respectively.The haplotype diversity ranged from 0.682 to 0.835,and the nucleotide diversity ranged from 0.00849 to 0.01167.There were 32 haplotypes in all sequences,which could be divided into clades A,B,C and E,however,most of the individuals belonged to clades B (51.2%) and E (37.6%).The phylogenetic tree results showed that four high quality chicken breeds could be classified as 4 branches which were consistent with the haplotypes classification results.The results indicated that the four high quality chicken populations from Qingyuan had relatively high haplotype and nucleotide diversity and likely shared two or more common maternal lineages.     

Genetic Diversity Analysis of Shaanxi Moschus berezovskii Based on mtDNA Cytb Gene and D-loop Region Sequence

【Objective】 This study was aimed to explore the genetic diversity of Shaanxi Moschus berezovskii population,and understand the genetic information of Moschus berezovskii.【Method】 The hair of Moschus berezovskii was collected to extract DNA,the mitochondrial DNA(mtDNA) cytochrome b(Cytb) gene and D-loop sequences of 43 Moschus berezovskii individuals were determined,and the base composition was counted.All sequences were integrated and compared using ClustalX 2.0 software to obtain nucleotide polymorphic sites (SNPs) in the population.The nucleotide diversity (Pi),number of haplotype (H),haplotype diversity (Hd) and average number of nucleotide differences (K) were calculated by DNASP 5.10 software.The genetic distance among different haplotypes of Cytb gene and D-loop sequences was calculated by Mega 7.0 software,and Neighbor-Joining (NJ) phylogenetic tree was constructed.【Result】 The AT content of Cytb gene and D-loop region were higher than GC content,indicating there was bias in base composition.There were 241 and 383 SNPs of Cytb gene and D-loop region,respectively.The nucleotide diversity of Cytb gene and D-loop region were 0.28343 and 0.07707,and the haplotype diversity was 0.983 and 0.975,respectively,indicating that the population genetic diversity was rich.The genetic distances of 35 haplotypes of Cytb gene ranged from 0.002 to 0.831,and 29 haplotypes of D-loop region ranged from 0.006 to 1.342.The phylogenetic tree showed that there were two mitochondrial lineages,indicating that there were two mitochondrial maternal origins.The evolutionary analysis of D-loop region also supported this conclusion.【Conclusion】 The nucleotide diversity and haplotype diversity of Moschus berezovskii population were high,and the genetic diversity was rich.At the same time further supported the view of Moschus berezovskii and Moshus moschiferus belonged to a branch of the view.     

基于三种分子标记的栽培金鸡菊遗传多样性及亲缘关系分析

利用ISSR、核基因ITS2、叶绿体基因psbA-trnH和trnL-F三种分子标记对100个国内外广为种植的栽培金鸡菊(Coreopsis)种质进行遗传多样性和亲缘关系分析，以期为栽培金鸡菊的分类鉴定、育种及指纹图谱构建提供更多分子依据。结果表明：三种分子标记均显示沙漠金鸡菊与其余材料亲缘关系较远；12条ISSR引物扩增出总条带153个，多态性条带149个，多态性条带百分比为97.39%，在遗传距离为0.664处整体可划分为4类；ITS2,psbA-trnH和trnL-F序列大小分别为171bp~175bp,252bp~426bp和698bp~703bp；基于psbA-trnH和trnL-F序列的母系溯源整体可分为6类，二者合并后定义了9个单倍型，两色组和歧序组是具有特殊舌状花色的金鸡菊品种重要的母系材料，轮叶金鸡菊‘月光’和短毛金鸡菊‘虹光’等品种源于远缘杂交；ITS2序列将整体划分为5类，定义了63个单倍型，大部分单倍型只对应一个种质，ITS2序列有望作为金鸡菊品种鉴定的DNA条形码。     

Phylogenetic analysis for the Seoul National University (Minnesota) miniature pig by mitochondrial DNA sequence polymorphism

Seoul National University (SNU) miniature pigs are originated from the Minnesota miniature pig. This study was conducted to investigate the maternal origin of SNU (Minnesota) miniature pigs and their phylogenetic relationships by analyzing the mitochondrial DNA (mtDNA) D‐loop (control region) sequence. Two mtDNA D‐loop sequences of the SNU miniature pigs were identified. On an unweighted pair‐group method with an arithmetic mean (UPGMA) phylogenetic tree analysis, the large white was the pig breed closest to the SNU miniature pig, and the pairwise distance analysis showed the same result. While mtDNA sequences of 4 pig breeds which were used to establish Minnesota miniature pig were not known, our result might be different from the history of the Minnesota miniature pig development. In conclusion, we thought that some haplotypes of the Minnesota miniature pig maternally were originated from the Large white pig, or that wild pigs had similar mtDNA sequences to the Large white pig, and all SNU miniature pigs were derived from this colony.     

Genetic diversity of Bangladeshi native chickens based on complete sequence of mitochondrial DNA D-loop region

ABSTRACT

1. The aim of this study was to explore genetic diversity and possible origin of Bangladeshi (BD) native chickens. The complete mtDNA D-loop region was sequenced in 60 chickens representing five populations; naked neck, full feathered, Aseel, Hilly and autosomal dwarf. The 61 reference sequences representing different domestic chicken clades in China, India, Laos, Indonesia, Myanmar, and other Eurasian regions were included. The mtDNA D-loop sequence polymorphism and maternal origin of five BD populations were analysed.

2. A total of 35 polymorphic sites, and 21 haplotypes were detected in 60 mtDNA D-loop sequences. The haplotype and nucleotide diversity of the five populations were 0.921 ± 0.018 and 0.0061 ± 0.0019, respectively. Both mtDNA network and phylogenetic analysis indicated four clades (four haplogroups) in BD populations (21 haplotypes) along with 61 reference haplotypes. Clade E contained the most individuals (20) and haplotypes (11) of BD chickens, followed by clade D (17, 6), clade C (12, 2) and clade F (11, 2), respectively.

3. The higher number of unique haplotypes found in Yunnan, China, suggested that the origin of BD chickens was in this region. The haplotypes from different haplogroups were introduced in Bangladeshi chickens from India, China and Myanmar. The phylogenetic tree showed a close relationship of BD chickens with the clusters from India, China, Myanmar and Laos, and indicated the dispersion of BD chickens from these sources. The phylogenetic information revealed high genetic diversity of BD chickens because of their origin from different lineages with high genetic variation and distance, which was determined from four cluster and neighbour-joining trees.

4. In conclusion, BD populations had high genetic diversity. The mtDNA network profiles and phylogenetic trees showed multiple maternal origins of BD chickens from India, China, Myanmar and Laos.     

不同地区褐黄血蜱的基因变异及遗传进化分析

为探究不同区域褐黄血蜱的基因变异情况及其遗传进化关系，试验以采集自湖南、河南省的20只褐黄血蜱为研究对象，通过PCR扩增其内转录间隔区Ⅱ（ITS-2）和烟酰胺脱氢酶亚基Ⅰ（nad1）基因序列，并对所获序列进行基因变异分析；在所获ITS-2和nad1基因序列的基础上，对不同地区褐黄血蜱的遗传进化关系进行分析，并利用ITS-2和nad1基因序列分别构建褐黄血蜱的系统进化树。结果显示，褐黄血蜱ITS-2基因序列长度均为1 160 bp，nad1基因序列长度均为285 bp；两省褐黄血蜱ITS-2及nad1基因的种内差异分别为0~1.9%和0~0.4%；湖南省褐黄血蜱的种内差异分别为0~1.4%和0~0.4%，而河南省的种内差异分别为0~1.2%和0~0.4%；两省褐黄血蜱ITS-2及nad1基因的种间差异分别为37.0%~52.0%和13.6%~24.8%。系统进化树结果显示，所有来自于两省的褐黄血蜱共处于同一分支上。结果表明，来自于两省的褐黄血蜱之间均存在基因变异的现象，但湖南省褐黄血蜱的基因变异程度和遗传多样性均高于河南省；两省褐黄血蜱之间的亲缘关系较近，暗示两省褐黄血蜱之间有基因交流，未出现遗传分化。     

4个引进山羊品种mtDNA控制区序列变异和系统发生关系研究

本研究测定了四川4个引进山羊品种24个个体的线粒体控制区全序列,并从GenBank获得山羊属2个野山羊种的2每控制区序列。利用MEGA2．0软件构建分子系统发育无根树。序列分析表明:山羊控制区线粒体控制全序列长度为1 212bp或1 213 bp,A+T含量占59．9％,其中64个核苷酸位点存在变异(约占5．28％),核苷酸多样度为 1．731％,这些差异共定义了16种单倍型,单倍型多样性为0．913±0．048。安哥拉山羊、波尔山羊都有自己独特的单倍型,与其他品种间都没有共享类型。使用NJ法构建了系统发育树,结果表明:2个野山羊种中,角(?)羊与家养山羊的关系相对较近,4个家养山羊品种有2个母系来源,在4个家养山羊品种内部,安哥拉山羊的分化要比其他3个品种早。     

Genetic diversity of mtDNA D-loop sequences in four native Chinese chicken breeds

1. To explore the genetic diversity of Chinese indigenous chicken breeds, a 585 bp fragment of the mitochondrial DNA (mtDNA) region was sequenced in 102 birds from the Xichuan black-bone chicken, Yunyang black-bone chicken and Lushi chicken. In addition, 30 mtDNA D-loop sequences of Silkie fowls were downloaded from NCBI. The mtDNA D-loop sequence polymorphism and maternal origin of 4 chicken breeds were analysed in this study.

2. The results showed that a total of 33 mutation sites and 28 haplotypes were detected in the 4 chicken breeds. The haplotype diversity and nucleotide diversity of these 4 native breeds were 0.916 ± 0.014 and 0.012 ± 0.002, respectively. Three clusters were formed in 4 Chinese native chickens and 12 reference breeds. Both the Xichuan black-bone chicken and Yunyang black-bone chicken were grouped into one cluster. Four haplogroups (A, B, C and E) emerged in the median-joining network in these breeds.

3. It was concluded that these 4 Chinese chicken breeds had high genetic diversity. The phylogenetic tree and median network profiles showed that Chinese native chickens and its neighbouring countries had at least two maternal origins, one from Yunnan, China and another from Southeast Asia or its surrounding area.