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101.
对来自新疆不同地区的 12个甜菜坏死黄脉病毒 (BNYVV)分离物的核酸组分进行RT PCR分析表明 ,不同地区的BNYVV分离物RNA组分有一定差异。塔城、奇台和石河子 14 5团的BNYVV分离物含有RNA1、RNA2、RNA3和RNA4 ;库尔勒地区的BNYVV分离物还含有RNA5 ;石河子甜菜研究所病圃的BNYVV分离物只含有RNA1和RNA2。对RNA1- 4的RT -PCR产物进行SSCP分析还表明 ,新疆的所有BNYVV分离物既不同于美国的BN TX ,也不同于我国黑龙江的He分离物 ,其内部也存在明显的遗传分化 ,将新疆的 12个BNYVV分离物初步归为Ⅰ、Ⅱ、Ⅲ、Ⅳ共 4个类群。Ⅰ类群 :石河子分离物S1、S2 ;Ⅱ类群 :塔城T3、T6、T7和T8分离物 ;Ⅲ类群 :库尔勒K1、K2、K4、K5 ;Ⅳ类群 :奇台Q1、Q2分离物。而且这种遗传分化有明显的地域分布性。 相似文献
102.
Six1基因是调控肌肉形成过程中的重要基因。为研究Six1作为肉鸭生长发育候选基因的可行性,本实验以42日龄大型肉鸭为研究对象,采用PCR-SSCP技术检测肉鸭Six1基因第2外显子的多态性,并对所检测到的多位点组成的基因型与肉鸭屠体性状进行关联性分析。结果表明:在鸭Six1基因的编码区第729 bp处存在C→T突变,属同义突变,该突变位点在大型肉鸭群体中表现为AA与AB 2种基因型。肉鸭AA和AB基因型间,胸肌重、腿肌重和其他屠体性状差异不显著(P>0.05)。以上结果表明,鸭Six1基因第2外显子区没有适用于遗传标记的多态位点。 相似文献
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104.
基于ND4基因部分片段探讨中国4个家驴品种的母系构成 总被引：1，自引：0，他引：1
为了分析中国家驴的遗传多样性,对保种和开发利用这一固有遗传资源提供有益帮助,并对其母性起源提供一些基础资料,作者对我国4个家驴品种(德州、凉州、云南、蒙古)209个个体的mtDNAND4基因编码区409bp片段进行了扩增、单链构象多态(SSCP)检测与测序分析,共检测到5种单倍型8个多态位点,其单倍型多样度为0.4699,核苷酸多样度为0.00308,表明我国家驴的遗传多态性比较丰富。通过对各单倍型序列按照脊椎动物线粒体编码规则翻译成氨基酸序列进行比对发现,部分核苷酸变异引起了氨基酸的变异。构建的简化加权中值网络聚类图显示,4个家驴品种的样品来自两个母系源头,并且,4个中国家驴品种都是由这两个母性世系混杂而成的,即未发现由同一种世系构成的品种。这与以前基于D-loop区序列对于中国家驴的研究结果相似,即地理位置、世系构成以及母性起源之间没有明显的相互关系。 相似文献
105.
Jianxing Chen Zhenhua Song Meijie Rong Lingjiang Min Yujiang Sun 《Livestock Science》2009,126(1-3):306-309
The aim of this study was to investigate the effects of haplotypes in Cytb (Cytochrome b) gene on growth traits in three Chinese donkey breeds, Yunnan donkey (YN), Dezhou donkey (DZ) and Liangzhou donkey (LZ). The samples were genotyped for the Cytb gene by single strand conformation polymorphism (SSCP), and association analysis was conducted with growth traits. The results show that in most cases the effects of the gene on growth traits were not significant and that for the three different donkey breeds, the effects of the gene are different. For YN donkeys, there was a significant effect of the gene on the rump width (P < 0.05) and the effect of genotype AA was larger than that of BB genotype (1.6 cm and 5.4% of the trait mean in YN donkeys, P < 0.05). For DZ donkeys, the effect of gene on body height was significant (P < 0.05). The results also verify that the SSCPs are caused by two cytosine to thymine and one guanine to adenine transitions, corresponding to amino acid substitutions of leucine for proline (L ↔ P) and isoleucine for valine (I ↔ V). 相似文献
106.
促卵泡素（follicle stimulating hormone, FSH）对刺激动物卵泡发育和促进精子生成具有重要作用,但有关牛科物种FSH基因的群体遗传特征还不十分清楚。本文针对FSHβ基因外显子1和外显子2,采用PCR SSCP结合PCR产物直接测序技术对353头水牛(来自11个水牛群体)、30头牦牛和30头大额牛样品进行了群体变异检测,并结合NCBI数据库中已发表的普通牛、山羊和绵羊等物种同源序列进行了群体遗传和生物信息学分析。在FSHβ基因外显子1中,水牛中发现1个核苷酸替换和1个缺失,即c-49A>G和c-31delG;其中,SNP49在河流型和沼泽型水牛中均存在,等位基因c-49A为优势等位基因,而c-31delG只存在于沼泽型水牛中,且为杂合状态,基因频率为0.077。在牦牛外显子1中检测到c-37G>A和c-12T>C替换,且为连锁遗传的,而在大额牛外显子1中未检测到SNP位点。在FSHβ基因外显子2中,水牛中发现c132G>A替换,该位点在河流型和沼泽型水牛均存在,但等位基因频率在两类水牛间不一致。在牦牛外显子2中检测到c9C>T和c21C>T替换,该替换也存在于普通牛中;大额牛外显子2为单态,未见SNP位点。生物信息学分析显示,在一些牛科物种FSHβ基因外显子2中发现的SNP位点均为同义替换,揭示了其序列的高度保守性。在牛科物种中,山羊和绵羊FSHβ基因第36位密码子编码氨基酸与其他物种不同,可作为区分它们的遗传标记。 相似文献
107.
Association of citrus psorosis B symptoms with a sequence variant of the Citrus psorosis virus RNA 2
Citrus psorosis virus (CPsV), the type species of genus Ophiovirus, is the presumed causal agent of a bark scaling disease in citrus plants. CPsV virions are kinked filaments composed of three negative‐strand RNA molecules and a ～48‐kDa coat protein. The virus induces two different syndromes: psorosis A (PsA), characterized by limited bark scaling lesions in the trunk and main limbs, and a more aggressive form of the disease called psorosis B (PsB) with rampant bark lesions affecting even thin branches and chlorotic blotches in old leaves. In the greenhouse, the PsA and PsB syndromes can be induced by graft inoculating healthy citrus seedlings with non‐lesion or with lesion bark inoculum from PsA‐affected field trees. PsA‐ and PsB‐inducing CPsV sub‐isolates obtained by this procedure from the same tree showed identical single‐strand conformation polymorphism (SSCP) profiles in homologous segments of the RNAs 1 and 3, whereas segments of the RNA 2 enabled discrimination between PsA‐ and PsB‐associated sequence variants. SSCP analysis of the RNA 2 population present in different tissues of psorosis‐infected plants showed that: (i) PsA‐inducing isolates contain PsB‐associated sequence variants at low frequency, (ii) the PsB‐associated sequence variant is predominant in blistered twigs and gummy pustules affecting old leaves, characteristic of PsB isolates, and (iii) the PsB‐associated sequence variant accumulates preferentially in bark lesions of the trunk and limbs. SSCP analysis of the RNA 2 population also enabled monitoring of interference between PsA‐ and PsB‐associated variants in plants co‐inoculated with both psorosis types. 相似文献
108.
甘薯羽状斑驳病毒外壳蛋白基因的分子变异 总被引：4，自引：0，他引：4
应用单链构象多态性(single-strand conformation polymorphism,SSCP)技术结合核苷酸序列测定的方法,对我国甘薯主产区11个省份的甘薯羽状斑驳病毒(Sweet potato feathery mottle virus,SPFMV)外壳蛋白(CP)基因的分子变异情况进行了研究.结果表明,SPFMV CP基因的RT-PCR产物表现了较丰富的图谱类型,50个分离物共产生9种主要的SSCP带型;对显示不同带型的20个样品的CP基因进行了序列测定和进化树分析,CP基因核苷酸序列一致性为77.2％～99.9％.说明这些样品的SPFMV的CP基因存在较大的分子变异,可划分为EA、RC、O和C4个株系. 相似文献
109.
本研究根据鸡Apo VLDL-Ⅱ基因内含子Ⅰ的基因序列设计3对引物,分别采用PCR-RFLP、PCR-SSCP技术对文昌鸡、如皋黄鸡、丝羽乌骨鸡、安卡肉鸡及红色原鸡5个鸡种进行多态性研究。结果表明,鸡Apo VLDL-Ⅱ基因内含子Ⅰ存在4处突变,分别为:1950处G/A、2522处A/C、2705处A/C及2793处C/T。统计结果显示:安卡肉鸡基因型频率的分布与如皋黄鸡、红色原鸡存在显著差异,文昌鸡基因型频率的分布与乌骨鸡差异不显著,除安卡肉鸡外所有鸡种均处于Hardy-Weinberg平衡状态。 相似文献
110.
B. Qu H. P. Li J. B. Zhang T. Huang J. Carter Y. C. Liao P. Nicholson 《Plant pathology》2008,57(4):642-651
The genetic diversity and pathogenicity of isolates of Fusarium graminearum and F. asiaticum isolated from wheat heads in China were examined and compared with those of isolates of F. graminearum , F. asiaticum and F. meridionale from Europe, USA and Nepal. Genetic diversity was assessed by SSCP (single strand conformation polymorphism) and AFLP (amplified fragment length polymorphism) analysis and by molecular chemotyping. SSCP analysis of the Fg16F/Fg16R PCR amplicon differentiated F. graminearum , F. asiaticum and F. meridionale and revealed three haplotypes among sequence-characterized amplified region (SCAR) type 1 F. graminearum isolates. AFLP analysis showed a high level of genetic diversity and clustered the majority of Chinese isolates in one group along with other isolates of Asian origin. The second cluster contained F. graminearum isolates from China, Europe and the USA. Of the Chinese isolates, 79% were F. asiaticum and 81% of these were of the 3-AcDON chemotype, with only 9·5% of either chemotype 15-AcDON or NIV. All the Chinese and USA isolates of F. graminearum were 15-AcDON, whereas among the isolates from Europe, 21% were NIV and 8% were 3-AcDON chemotype. No evidence was found for possible differences in aggressiveness between F. graminearum and F. asiaticum . Highly aggressive isolates were present in each region and no evidence was found for any association between aggressiveness and geographical origin or chemotype among the isolates examined. No difference was observed in pathogenicity towards wheat seedlings between Chinese isolates and those from Europe, the USA or Nepal. 相似文献