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1.
用mtDNA D-环序列探讨蒙古和中国绵羊的起源及遗传多样性 总被引:16,自引:0,他引:16
为了在分子水平上探讨绵羊的起源,对中国和蒙古共20个绵羊群体、314只绵羊mtDNA D-环的部分序列进行了测定,结果表明:中国绵羊和蒙古绵羊mtDNA D-环区的部分序列中A、T、G、C含量没有明显的差别;蒙古绵羊的多态位点数(28.85%)略高于中国绵羊(24.22%);中国绵羊群体的单倍型多样度在青海藏羊、甘肃藏羊、甘肃高山细毛羊、青海细:色羊、甘南藏羊、小尾寒羊和滩羊群体中较高,但在湖羊和岷县黑裘皮羊中较低;蒙古绵羊的单倍型多样度在Bayad和Baidrag群体中最高,但在Gobi—Altai群体中最低。从总体上看,蒙古绵羊的遗传多样性要略高于中国绵羊,例如单倍犁比例的平均值为86.06%(142/185):78.83%(108/137),单倍型多样度(Hd)的甲均值为0.976:0.936,核苷酸多样度(Pi(π))的平均值为0.036:0.034,平均核苷酸差异数(k)的平均值为23.50:22.48~217个中国和蒙古绵羊的单倍型序列的系统发生分析表明,中国和蒙古绵羊均有3个母系起源,被定义为A、B和C3类主要的单倍型。其中A类单倍型在所有中国绵羊群体及绝大多数蒙古绵羊群体(9/11)中占优势,平均比例为58.73%;B类单倍型居中,为24.88%;C类单倍型最少,仅为16.59%。进一步从GenBank获得的91个绵羊D-环区的序列与中国和蒙古绵羊D-环区的单倍型的进行网络关系分析,发现欧洲摩弗仑羊(European mouflon,O.musimon)与中国和蒙古绵羊具有较近的亲缘关系,但没有发现塬羊(Argali.O.ammon)、盘羊(0.rignei bochariensis)和东方盘羊(0.ammon nigrimontana)对中国和蒙古绵羊起源有贡献的证据。 相似文献
2.
Pairwise Comparisons of Mitochondrial DNA Sequences in Subdivided Populations and Implications for Early Human Evolution 总被引:22,自引:4,他引:18
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We consider the effect on the distribution of pairwise differences between mitochondrial DNA sequences of the incorporation into the underlying population genetics model of two particular effects that seem realistic for human populations. The first is that the population size was roughly constant before growing to its current level. The second is that the population is geographically subdivided rather than panmictic. In each case these features tend to encourage multimodal distributions of pairwise differences, in contrast to existing, unimodal datasets. We argue that population genetics models currently used to analyze such data may thus fail to reflect important features of human mitochondrial DNA evolution. These may include selection on the mitochondrial genome, more realistic mutation mechanisms, or special population or migration dynamics. Particularly in view of the variability inherent in the single available human mitochondrial genealogy, it is argued that until these effects are better understood, inferences from such data should be rather cautious. 相似文献
3.
随着新的DNA聚合酶A家族成员的加入,家族内部的系统发育关系需要重新检查。分析显示:在真核生物演化的不同阶段,线粒体DNA聚合酶基因可能通过水平基因转移方式起源于不同类群的生物。原始真核生物线粒体DNA聚合酶基因可能来源于细菌,植物线粒体DNA聚合酶基因可能从质粒获得,而真菌和动物线粒体DNA聚合酶基因可能起源于T3/T7相关噬菌体。 相似文献
4.
Stela S. Lazarova Gaynor Malloch Claudio M.G. Oliveira Judith H��bschen Roy Neilson 《Journal of nematology》2006,38(4):404-410
The 18S ribosomal DNA (rDNA) and cytochrome oxidase I region of mitochondrial DNA (mtDNA) were sequenced for 24 Xiphinema americanum-group populations sourced from a number of geographically disparate locations. Sequences were subjected to phylogenetic analysis and compared. 18S rDNA strongly suggested that only X. pachtaicum, X. simile (two populations) and a X. americanum s.l. population from Portugal were different from the other 20 populations studied, whereas mtDNA indicated some heterogeneity between populations. Phylogenetically, based on mtDNA, an apparent dichotomy existed amongst X. americanum-group populations from North America and those from Asia, South America and Oceania. Analyses of 18S rDNA and mtDNA sequences underpin the classical taxonomic issues of the X. americanum-group and cast doubt on the degree of speciation within the X. americanum-group. 相似文献
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6.
厚壳贻贝养殖群体与野生群体线粒体DNA的遗传分析(英文) 总被引:2,自引:0,他引:2
采用线粒体DNA COI基因序列对厚壳贻贝2个养殖群体与2个野生群体的遗传多样性进行了研究。4个群体共获得30个单倍型。结果显示:在养殖群体中单倍型的数量和遗传多样性要比野生群体的低,可能是由于只有少量的有效父母本对养殖群体的遗传变异有贡献所致。养殖群体与当地野生群体之间也未发生显著的遗传分化,可能是因为它们之间存在基因流。在今后厚壳贻贝养殖过程中,本研究可以用在对养殖群体进行遗传监测,从而保证养殖群体的遗传多样性水平。 相似文献
7.
Miriam Baeta Carolina Nú?ez Sergio Cardoso Leire Palencia-Madrid Sergio Pi?eiro-Hermida Miren Arriba-Barredo María Jesús Villanueva-Millán Marian M. de Pancorbo 《PloS one》2015,10(12)
The Basque Diaspora in Western USA and Argentina represents two populations which have maintained strong Basque cultural and social roots in a completely different geographic context. Hence, they provide an exceptional opportunity to study the maternal genetic legacy from the ancestral Basque population and assess the degree of genetic introgression from the host populations in two of the largest Basque communities outside the Basque Country. For this purpose, we analyzed the complete mitochondrial DNA control region of Basque descendants living in Western USA (n = 175) and in Argentina (n = 194). The Diaspora populations studied here displayed a genetic diversity in their European maternal input which was similar to that of the Basque source populations, indicating that not important founder effects would have occurred. Actually, the genetic legacy of the Basque population still prevailed in their present-day maternal pools, by means of a haplogroup distribution similar to the source population characterized by the presence of autochthonous Basque lineages, such as U5b1f1a and J1c5c1. However, introgression of non-Basque lineages, mostly Native American, has been observed in the Diaspora populations, particularly in Argentina, where the quick assimilation of the newcomers would have favored a wider admixture with host populations. In contrast, a longer isolation of the Diaspora groups in USA, because of language and cultural differences, would have limited the introgression of local lineages. This study reveals important differences in the maternal evolutionary histories of these Basque Diaspora populations, which have to be taken into consideration in forensic and medical genetic studies. 相似文献
8.
B. A. Malyarchuk M. V. Derenko G. A. Denisova M. R. Nassiri E. I. Rogaev 《Russian Journal of Genetics》2002,38(4):434-438
Mitochondrial DNA (mtDNA) restriction polymorphism was examined in Turkmens, Eastern Iranians, and Ukrainians. The gene pools of all populations studied were characterized by the presence of European mtDNA lineages. Mongoloid component observed in Turkmen and Iranian populations with the frequencies of about 20% was represented by groups C, D, and E/G in Turkmens, and by M*, D, A, and B in Iranians. The relative positions of the populations studied, of populations from the Caucasus, Western Iran, and Russian populations from the Krasnodar krai and Belgorod oblast in the space of principal components revealed a geographically specific pattern of the population clustering. The data on mtDNA polymorphism indicated pronounced differentiation of Eastern and Western Iranians. The latter were characterized by a mtDNA group composition similar to that in Eastern Slavs. The historical role of the Caspian populations in the formation of the population of Southeastern Europe is discussed. 相似文献
9.
Angela Cannas Glendah Kalunga Clare Green Ludovica Calvo Patrick Katemangwe Klaus Reither Mark D. Perkins Leonard Maboko Michael Hoelscher Elizabeth A. Talbot Peter Mwaba Alimuddin I. Zumla Enrico Girardi Jim F. Huggett for the TB trDNA consortium 《PloS one》2009,4(9)
Background
Molecular diagnosis using urine is established for many sexually transmitted diseases and is increasingly used to diagnose tumours and other infectious diseases. Storage of urine prior to analysis, whether due to home collection or bio-banking, is increasingly advocated yet no best practice has emerged. Here, we examined the stability of DNA in stored urine in two populations over 28 days.Methodology
Urine from 40 (20 male) healthy volunteers from two populations, Italy and Zambia, was stored at four different temperatures (RT, 4°C, −20°C & −80°C) with and without EDTA preservative solution. Urines were extracted at days 0, 1, 3, 7 and 28 after storage. Human DNA content was measured using multi-copy (ALU J) and single copy (TLR2) targets by quantitative real-time PCR. Zambian and Italian samples contained comparable DNA quantity at time zero. Generally, two trends were observed during storage; no degradation, or rapid degradation from days 0 to 7 followed by little further degradation to 28 days. The biphasic degradation was always observed in Zambia regardless of storage conditions, but only twice in Italy.Conclusion
Site-specific differences in urine composition significantly affect the stability of DNA during storage. Assessing the quality of stored urine for molecular analysis, by using the type of strategy described here, is paramount before these samples are used for molecular prognostic monitoring, genetic analyses and disease diagnosis. 相似文献10.
11.
To assess the genetic diversity of Japanese native horse populations, we examined seven such populations using mitochondrial
DNA (mtDNA) and microsatellite analyses. Four reference populations of Mongolian horses and European breeds were employed
as other equids. In the mtDNA analysis, the control region (D-loop) of 411 bp was sequenced, and 12 haplotypes with 33 variable
sites were identified in the Japanese native horses. The phylogenetic tree constructed by haplogrouping and using worldwide
geographic references indicated that the haplotypes of the Japanese native horses were derived from six equid clusters. Compared
with the foreign populations, the Japanese native populations showed lower within-population diversity and higher between-population
differentiation. Microsatellite analysis, using 27 markers, found an average number of alleles per locus of 9.6 in 318 native
and foreign horses. In most native populations, the within-population diversity was lower than that observed in foreign populations.
The genetic distance matrix based on allelic frequency indicated that several native populations had notably high between-population
differentiation. The molecular coancestry-based genetic distance matrix revealed that the European populations were differentiated
from the Japanese and Mongolian populations, and no clear groups could be identified among the Japanese native horse populations.
The genetic distance matrices had few correlations with the geographic distribution of the Japanese native populations. Based
on the results of both mtDNA and microsatellite analyses, it could be speculated that each native population was formed by
the founder populations derived from Mongolian horses. The genetic construction of each population appears to have been derived
from independent breeding in each local area since the time of population fission, and this was accompanied by drastic genetic
drift in recent times. This information will help to elucidate the ancestry of Japanese native horses.
An erratum to this article can be found at 相似文献
12.
Mary Katherine Gonder Todd R. Disotell John F. Oates 《International journal of primatology》2006,27(4):1103-1127
Primatologists widely recognize chimpanzees as belonging to a single species, Pan troglodytes, which they traditionally have further divided into 3 subspecies: west African P. t. verus, central African P. t. troglodytes, and east African P. t. schweinfurthii. Previously, we suggested that the phylogeographic history of chimpanzees may be different from that implied by the widely used taxonomy of the species. We based the suggestion on only a limited sample of haplotypes from the first hypervariable region (HVRI) of mitochondrial (mt)DNA from chimpanzees in Nigeria. We have now compiled a more geographically comprehensive genetic database for chimpanzees, including samples obtained near the Niger and Sanaga Rivers. Our database is composed of 254 HVRI haplotypes from chimpanzees of known geographic origin, including 79 unique HVRI haplotypes from chimpanzees living in Nigeria and Cameroon. The genetic data provide clear evidence that a major phylogeographic break between chimpanzee lineages occurs near the Sanaga River in central Cameroon and suggest the need for a reclassification of chimpanzees. 相似文献
13.
Andrianov B. V. Sorokina S. Yu. Gorelova T. V. Mitrofanov V. G. 《Russian Journal of Genetics》2003,39(6):630-635
Restriction fragment length polymorphism (RFLP) analysis has been used to evaluate mitochondrial DNA (mtDNA) variation in 12 sibling species forming the Drosophila virilis species group. The variation thresholds corresponding to the interspecific and interstrain levels have been determined. The results indicate that interspecific hybridization has significantly contributed to the evolutionary history of the virilis species group. 相似文献
14.
采用PCR技术获得了贵州7个南蝠(Ia io)自然种群42个个体的线粒体DNA控制区全序列,长度为1256~1340 bp.对控制区结构进行分析,识别了其延伸的终止结合序列区(包括ETAS1和ETAS2元件)、中央保守区(包括F、E、D、C、B元件)和保守序列区(包括CSB1、CSB2和CSB3元件);同时,在延伸的终止结合序列区还发现了若干能形成发夹结构的主体序列TACAT—ATGTA.在7个自然种群42个个体中共定义了16个单倍型.遗传多样性分析表明:贵州南蝠种群具有较高的单倍型多样性(h=0.945)和中等的核苷酸多样性(π=0.012).基因流、AMOVA和系统进化树分析表明贵州这7个南蝠自然群体间没有发生遗传分化. 相似文献
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16.
Peizhong MaoPatience Gallagher Samira NedungadiMaria Manczak Ulziibat P. shirendebSteven G. Kohama Betsy FergusonByung S. Park P. Hemachandra Reddy 《生物化学与生物物理学报:疾病的分子基础》2012,1822(2):111-119
The purpose of this study was to determine the relationship between mitochondrial DNA (mtDNA) deletions, mtDNA content and aging in rhesus monkeys. Using 2 sets of specific primers, we amplified an 8 kb mtDNA fragment covering a common 5.7 kb deletion and the entire 16.5 kb mitochondrial genome in the brain and buffy-coats of young and aged monkeys. We studied a total of 66 DNA samples: 39 were prepared from a buffy-coat and 27 were prepared from occipital cortex tissues. The mtDNA data were assessed using a permutation test to identify differences in mtDNA, in the different monkey groups. Using real-time RT-PCR strategy, we also assessed both mtDNA and nuclear DNA levels for young, aged and male and female monkeys. We found a 5.7 kb mtDNA deletion in 81.8% (54 of 66) of the total tested samples. In the young group of buffy-coat DNA, we found 5.7 kb deletions in 7 of 17 (41%), and in the aged group, we found 5.7 kb deletions in 12 of 22 (54%), suggesting that the prevalence of mtDNA deletions is related to age. We found decreased mRNA levels of mtDNA in aged monkeys relative to young monkeys. The increases in mtDNA deletions and mtDNA levels in aged rhesus monkeys suggest that damaged DNA accumulates as rhesus monkeys age and these altered mtDNA changes may have physiological relevance to compensate decreased mitochondrial function. 相似文献
17.
Pairwise Comparisons of Mitochondrial DNA Sequences in Stable and Exponentially Growing Populations 总被引:47,自引:0,他引:47
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We consider the distribution of pairwise sequence differences of mitochondrial DNA or of other nonrecombining portions of the genome in a population that has been of constant size and in a population that has been growing in size exponentially for a long time. We show that, in a population of constant size, the sample distribution of pairwise differences will typically deviate substantially from the geometric distribution expected, because the history of coalescent events in a single sample of genes imposes a substantial correlation on pairwise differences. Consequently, a goodness-of-fit test of observed pairwise differences to the geometric distribution, which assumes that each pairwise comparison is independent, is not a valid test of the hypothesis that the genes were sampled from a panmictic population of constant size. In an exponentially growing population in which the product of the current population size and the growth rate is substantially larger than one, our analytical and simulation results show that most coalescent events occur relatively early and in a restricted range of times. Hence, the "gene tree" will be nearly a "star phylogeny" and the distribution of pairwise differences will be nearly a Poisson distribution. In that case, it is possible to estimate r, the population growth rate, if the mutation rate, mu, and current population size, N0, are assumed known. The estimate of r is the solution to ri/mu = ln(N0r) - gamma, where i is the average pairwise difference and gamma approximately 0.577 is Euler's constant. 相似文献
18.
Native American Mitochondrial DNA Analysis Indicates That the Amerind and the Nadene Populations Were Founded by Two Independent Migrations 总被引:49,自引:0,他引:49
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A. Torroni T. G. Schurr C. C. Yang EJE. Szathmary R. C. Williams M. S. Schanfield G. A. Troup W. C. Knowler D. N. Lawrence K. M. Weiss D. C. Wallace 《Genetics》1992,130(1):153-162
Mitochondrial DNAs (mtDNAs) from 167 American Indians including 87 Amerind-speakers (Amerinds) and 80 Nadene-speakers (Nadene) were surveyed for sequence variation by detailed restriction analysis. All Native American mtDNAs clustered into one of four distinct lineages, defined by the restriction site variants: HincII site loss at np 13,259, AluI site loss at np 5,176, 9-base pair (9-bp) COII-tRNA(Lys) intergenic deletion and HaeIII site gain at np 663. The HincII np 13,259 and AluI np 5,176 lineages were observed exclusively in Amerinds and were shared by all such tribal groups analyzed, thus demonstrating that North, Central and South American Amerinds originated from a common ancestral genetic stock. The 9-bp deletion and HaeIII np 663 lineages were found in both the Amerinds and Nadene but the Nadene HaeIII np 663 lineage had a unique sublineage defined by an RsaI site loss at np 16,329. The amount of sequence variation accumulated in the Amerind HincII np 13,259 and AluI np 5,176 lineages and that in the Amerind portion of the HaeIII np 663 lineage all gave divergence times in the order of 20,000 years before present. The divergence time for the Nadene portion of the HaeIII np 663 lineage was about 6,000-10,000 years. Hence, the ancestral Nadene migrated from Asia independently and considerably more recently than the progenitors of the Amerinds. The divergence times of both the Amerind and Nadene branches of the COII-tRNA(Lys) deletion lineage were intermediate between the Amerind and Nadene specific lineages, raising the possibility of a third source of mtDNA in American Indians. 相似文献
19.
S. Klinbunga D.J. Penman B.J. McAndrew A. Tassanakajon 《Marine biotechnology (New York, N.Y.)》1999,1(2):113-121
Mitochondrial DNA restriction fragment length polymorphism (mtDNA-RFLP) was utilized for determination of genetic variation
and population structure in Penaeus monodon collected from Satun (the Andaman Sea) and Surat and Trat (the Gulf of Thailand). Twenty-eight composite haplotypes were
generated from 52 restriction profiles of P. monodon mtDNA digested with 11 restriction endonucleases. The size of the entire P. monodon mitochondrial genome was estimated to be 15.913 ± 0.177 kb. The average haplotype diversity in P. monodon was 0.864, whereas the mean nucleotide diversity within populations was 2.51%, 2.22%, and 1.91% for Satun, Trat, and Surat,
respectively. Geographic heterogeneity analysis indicated population differentiation between P. monodon from the Andaman Sea and P. monodon from the Gulf of Thailand (p < .0001). On the basis of the high genetic diversity level of P. monodon in Thailand, the Satun and Trat P. monodon populations from the west and east of the pennisula were selected to be founder stocks in our selective breeding program.
Received February 23, 1998; accepted September 30, 1998. 相似文献
20.
Restriction enzyme analysis was employed in studying the mitochondrial DNA (mtDNA) ATPase6/ND4L region in several Northeast Asian populations of resident lake char of the genus Salvelinus. On evidence of mitotypes, genetic similarity was assumed for populations of neiva (Ueginskoe Lake), lake resident char from the northern coast of the Sea of Okhotsk (Mak-Mak Lake and Elekchanskie lakes), and dolly varden. Mitotype AAAA proved to be common for these populations. Lake char populations of the Juliet and Maxi lakes (the basin of the Kolyma River) had mitotype DBAA, which is similar to mitotype DBAB observed earlier in Taranetz char from Chukotka. The divergence between mitotypes AAAA and DBAA was estimated at 0.3%. Different origins were assumed for the lake resident char populations from the basins of the Sea of Okhotsk and of the Kolyma River, the former originating in the Pacific and the latter, in the Arctic basins. 相似文献