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1.
We have analyzed 105 autosomal polymorphic short tandem repeat (STR) loci for nine East and South-eastern Asian populations (two Japanese, five Han Chinese, Thai, and Burmese populations) and a Caucasian population using a multiplex PCR typing system. All the STR loci are genomewide tetranucleotide repeat markers of which the total number of observed alleles and the observed heterozygosity were 756 and 0.743, respectively, for Japanese populations. Phylogenetic analysis for these allele frequency data suggested that the Japanese populations are more closely related with southern Chinese populations than central and/or northern ones. STRUCTURE program analysis revealed the almost clearly divided and accountable population structure at K=2–6, that the two Japanese populations always formed one group separated from the other populations and never belong to different groups at K≥3. Furthermore, our new allele frequency data for 91 loci were analyzed with those for 52 worldwide populations published by previous studies. Phylogenetic and multidimensional scaling (MDS) analyses indicated that Asian populations with large population size (six Han Chinese, three Japanese, two Southeast Asia) formed one distinct cluster and are closer to each other than other ethnic minorities in east and Southeast Asia. This pattern may be the caviar of comparing populations with greatly differing population sizes when STR loci were analyzed.  相似文献   

2.
Tsunoda K  Sato K 《Biochemical genetics》2001,39(11-12):407-416
The nonhemoglobin erythrocytic X-protein polymorphism consisting of two phenotypes called X-positive [X(+)] and X-negative [X(-)] was determined in 576 unrelated healthy native sheep of East Asia, using one-dimensional and horizontal starch gel electrophoresis. A striking difference in the frequency of the X allele coding dominantly for the X(+) type between the northern and southern populations of native East Asian sheep divided by the boundary of the Himalaya Mountains was seen (P < 0.0001). The X allele frequency ranged from 0 to 0.0438 with an average of 0.0323 in the northern population examined, consisting of the Bhyanglung, Baruwal, Yunnan, and Khalkhas sheep belonging to the Tibetan and Mongolian sheep groups. In contrast, the frequency of the same allele was in the range of 0.2037-0.4655 and the mean frequency was 0.2998 in the southern population tested, consisting of the Bengal, Kagi, Lampuchhre, Vietnamese, and Myanmar sheep, which belong to the Indian sheep group. This finding suggests that the X allele appears to be an Indian sheep marker and is potentially important in phylogenetic studies on native sheep populations, especially in East Asia.  相似文献   

3.
Using five microsatellite loci, genotyping and genetic diversity estimates were obtained for nine samples representing seven common carp breeds most widespread in Russia. For comparison, the samples of Amur wild common carp (Cyprinus carpio haematopterus) and a sample of European Hungarian carp were used. In the samples examined (n = 148) a total of 78 alleles were revealed. The highest mean allele number per locus (7.3) was identified in Amur wild common carp, while the lowest number was found in Cherepets carps (4.0). In different breeds, the observed heterozygosities varied from 0.819 (Altai carp) to 0.651 (Cherepets scaly carp). Three out of five microsatellite loci (MFW-24, MFW-28, and MFW-19) revealed a high level of population differentiation. In the dendrogram of genetic differences, all breeds clustered into two groups. One of these groups was composed of the two strains of Ropsha carp, Stavropol carp, Amur wild common carp, and the two samples of Cherepets carp. The second cluster included Altai carp (Priobskii and Chumysh populations), two Angelinskii carp breeds (mirror and scaly), and Hungarian carp. The pairs of breeds/populations/strains, having common origin, were differentiated. Specifically, these were two populations of Altai carp, two strains of Ropsha carp, as well as the breeds of Angelinskii and Cherepets carps. The reasons for genetic differentiation of Russian common carp breeds, as well as the concordance of the evolutionary histories of these breeds, some of which originated from the European breeds, while the others contain substantial admixture of the Amur wild common carp, are discussed.  相似文献   

4.
Geng R  Chang H  Wang L  Tsunoda K  Yang Z  Sun W  Ji D  Li Y 《Biochemical genetics》2007,45(3-4):263-279
Variations of four sheep populations in China were examined by multiloci electrophoresis, and similar data are quoted to analyze the degree of genetic differentiation of native sheep populations in East and South Asia. Among 15 populations, the average heterozygosity is 0.2746, and the effective number of alleles is 1.559. Mongolian sheep possess the highest genetic diversity, and diversity decreases sequentially in the Chinese, Vietnamese, Bangladeshi, and Nepalese populations. Coefficients of genetic differentiation are 0.0126–0.3083, with an average of 0.148, demonstrating that the major genetic variation (85%) exists within populations. Genetic identity and genetic distance all show relatively low genetic differentiation. No relationship was found between geographic distance and genetic distance. Gene flow is common among the mass of populations, which leads to the inconsistency between geographic distance and genetic distance. The 15 native sheep populations in East and South Asia can be divided into two groups, one group including part of the Chinese and Mongolian populations and another including theYunnan population of China and part of the Nepalese and Bangladeshi populations. Other populations did not separate into groups, merging instead into the two main groups.  相似文献   

5.
Domestic sheep in Kazakhstan may provide an interesting source of genetic variability due to their proximity to the center of domestication and the Silk Route. Additionally, those breeds have never been compared to New World sheep populations. This report compares genetic diversity among five Kazakhstan (KZ) and 13 United States (US) sheep breeds (N = 442) using 25 microsatellite markers from the FAO panel. The KZ breeds had observed and expected measures of heterozygosity greater than 0.60 and an average number of alleles per locus of 7.8. In contrast, US sheep breeds had observed heterozygosity ranged from 0.37 to 0.62 and had an average number of alleles of 5.7. A Bayesian analysis indicated there were two primary populations (K = 2). Surprisingly, the US breeds were near evenly split between the two clusters, while all of the KZ breeds were placed in one of the two clusters. Pooling breeds within country of sample origin showed KZ and US populations to have similar levels of expected heterozygosity and the average number of alleles per locus. The results of breeds pooled within country suggest that there was no difference between countries for these diversity measures using this set of neutral markers. This finding suggests that populations’ geographically isolated from centers of domestication can be more diverse than previously thought, and as a result, conservation strategies can be adjusted accordingly. Furthermore, these results suggest there may be limited need for countries to alter the protocols for trade and exchange of animal genetic resources that are in place today, since no one population has a unique set of private alleles.  相似文献   

6.
We analyzed the population genetic structure and demographic history of 20 Lymantria dispar populations from Far East Asia using microsatellite loci and mitochondrial genes. In the microsatellite analysis, the genetic distances based on pairwise FST values ranged from 0.0087 to 0.1171. A NeighborNet network based on pairwise FST genetic distances showed that the 20 regional populations were divided into five groups. Bayesian clustering analysis (K = 3) demonstrated the same groupings. The populations in the Korean Peninsula and adjacent regions, in particular, showed a mixed genetic pattern. In the mitochondrial genetic analysis based on 98 haplotypes, the median‐joining network exhibited a star shape that was focused on three high‐frequency haplotypes (Haplotype 1: central Korea and adjacent regions, Group 1; Haplotype 37: southern Korea, Group 2; and Haplotype 90: Hokkaido area, Group 3) connected by low‐frequency haplotypes. The mismatch distribution dividing the three groups was unimodal. In the neutral test, Tajima's D and Fu's FS tests were negative. We can thus infer that the Far East Asian populations of L. dispar underwent a sudden population expansion. Based on the age expansion parameter, the expansion time was inferred to be approximately 53,652 years before present (ybp) for Group 1, approximately 65,043 ybp for Group 2, and approximately 76,086 ybp for Group 3. We propose that the mixed genetic pattern of the inland populations of Far East Asia is due to these expansions and that the inland populations of the region should be treated as valid subspecies that are distinguishable from other subspecies by genetic traits.  相似文献   

7.
Allele and genotype frequency distributions of prion protein (PrP) polymorphisms at three codons, 136, 154, and 171, in East Asian sheep were determined by PCR–RFLP analysis using 553 animals from nine local breeds of the northern group and four local breeds of the southern group. Based on the genotype distribution, the risk score for scrapie was estimated. Among the local breeds, ARQ appeared predominantly (0.7701–1), followed by ARH and ARR. From such a biased allele distribution, it was difficult to ascertain the prevalent genetic relationships. A marked difference in allele frequencies between the northern and southern groups was seen (P < 0.0001). The East Asian sheep had ARQ at the highest frequency (0.8834); in European sheep it was 0.5317. According to an assessment of scrapie risk in the PrP genotype classes, the predominant ARQ/ARQ in East Asian sheep corresponded to the risk score of R4. This finding suggests that East Asian sheep have a high level of genetic susceptibility to scrapie.  相似文献   

8.
Studies of domestic animals are performed on breeds, but a breed does not necessarily equate to a genetically defined population. The division of sheep from three native and four modern Baltic sheep breeds was studied using 21 microsatellite loci and applying a Bayesian clustering method. A traditional breed-wise approach was compared to that relying on the pattern of molecular diversity. In this study, a breed was found to be inconsistent with a distinct genetic population for three reasons: (i) a lack of differentiation between modern Baltic breeds, since the majority of the studied sheep formed a single population; (ii) the presence of individuals of foreign ancestry within the breed; and (iii) an undefined local Saaremaa sheep was referred to as a breed, but was shown to consist of separate populations. In the breed-wise approach, only the clearly distinct Ruhnu sheep demonstrated low within-breed variation, although the newly identified Saaremaa populations also have low variability. Providing adequate management recommendations for the Saaremaa sheep is not possible without further studies, but the potential harmful effects of inbreeding in the Ruhnu sheep could be reduced through the use of two genetically related Saaremaa populations. In other breeds, excessive crossing appears to be a larger concern than inbreeding. Assigning individuals into populations based on the pattern of genetic diversity offers potentially unbiased means of elucidating the genetic population structure of species. Combining these genetic populations with phenotypic and aetiological data will enable formulation of the most informed recommendations for gene resource management.  相似文献   

9.
The allele frequency distributions of six STR loci (D3S1358, D16S539, THOI, D8S1179, LPL, and HUMvWFII) used in forensic practice were analyzed in populations of Sakha (Yakutia): three ethnogeographical groups of Sakha (Yakuts), Evenks, Yukagirs, Dolgans, and Russians. There were significant differences between Russians and all other populations by five markers. The total discriminating power (PD) of the locus system studied was assessed for each population. The interpopulation genetic difference (F ST) was 0.005. Data on the allelic polymorphism of the above STR loci were used to analyze phylogenetic relationships among the populations of Sakha and those of other regions: East Europe, South Siberia, Chukotka, and Kamchatka.  相似文献   

10.
Herein, genetic relationships among five breeds of Bulgarian sheep were estimated using microsatellite markers. The total number of alleles identified was 226 at the 16 loci examined. D(A) distance values were used for phylogenetic tree construction with the UPGMA algorithm. The two Tsigai and two Maritza populations were found to be geneticallvery closely related to each other y (0.198, and 0.258 respectively). The Pleven Black Head population was distinct from the other four. These results could be useful for preserving genes in these breeds, thereby ensuring their preservation in Bulgaria.  相似文献   

11.
Miscanthus sinensis (Poaceae) is typical of many dominant grasses of East Asia. Due to its characteristics of fast growth and high biomass, Miscanthus, a C4 plant, has been long explored for the potential usage as biofuel. In this study, we described the development of nine microsatellite loci from M. sinensis for genetic studies. These new markers were tested in 25 individuals of five populations in three varieties. The number of alleles ranged from 3 to 8. The expected (H E) and observed (H O) heterozygosities were 0.37–0.78 and 0.05–0.52, respectively. All microsatellite loci are significantly deviated from Hardy–Weinberg expectations likely due to the population structure within samples. Linkage disequilibrium between four loci pairs were observed from the total 36 pairwise comparisons of loci. Cross-species transferability revealed that all loci can be applied to its closely related species, M. floridulus.  相似文献   

12.
Genetic variation and differentiation of 12 populations of Picea jezoensis from the Russian Far East were studied using 20 allozyme loci. The mean number of alleles per locus was 2.63, the percent of polymorphic loci was 88.1%, the observed heterozygosity was 0.181, and the mean value of expected heterozygosity amounted to 0.189. The values of expected heterozygosity of the northern and central mainland populations were higher than in the southern part of the natural range. A significant bias of Hardy–Weinberg heterozygosity to equilibrium heterozygosity (Heq) suggests that most of the mainland populations have recently experienced a severe expansion in population size while populations from Kamchatka Peninsula have undergone a reduction in population size. Unbiased Nei’s genetic distance values were low within and between the mainland and Sakhalin Island populations (DN=0.008). The largest values (DN=0.063) were found between the mainland/Sakhalin and Kamchatka Peninsula populations. Based on genetic distance, P. jezoensis and P. kamtschatkensis could be considered as distinct taxa, but P. ajanensis, P. microsperma, and P. komarovii do not warrant taxonomic recognition.  相似文献   

13.
Microsatellite–centromere recombination rates were estimated at 21 loci in relation to centromere of chromosomes in gynogenetic diploid lines induced from loaches Misgurnus anguillicaudatus of two different populations in Japan. All the microsatellite loci gave allelic segregation according to the Mendelian manner of inheritance in normal diploid families. Since loaches from the Kita population in the southern area of Hokkaido Island and those from the Memanbetsu population in the northern area, Hokkaido, Japan, were reported by previous genetic studies to be genetically diversified, map distances were compared between loaches from the two different populations. Three (Mado7, Mac3 and Mac49) of five loci, which could be compared inter-populationally, gave significantly different recombination rates, i.e., map distances. The results support the presence of genetic difference between the two populations. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

14.
This study is a part of long-term investigations devoted to the analysis of the gene pool of Dagestan ethnic groups. The phenotype (in %), gene, and haplotype frequencies in Kumyk ethnic group are reported. A total of 39 alleles and six haplotypes of 14 loci (AB0, Rhesus, P, Levis, Kell, HP, GC, C’3, TF, 6PGD, GLO1, ESD, ACP, and PGM1) of immunobiochemical genetic marker systems were examined. Rare haplotypes of the Rhesus system were identified, including CDE in the Karabudakhkent population with the frequency of 0.030, and Cde and cdE in the Dorgeli population with the frequencies of 0.034 and 0.38, respectively. Similarly to the other ethnic populations of Dagestan examined, Kukyk populations carried rare, albeit typically “Caucasoid” gene ACP1 c of the AcP1 locus. The frequency of this allele in the two populations was similar, constituting 0.031 for Karabudakhkent and 0.032 for Dorgeli. In Kumyks, allele frequencies of the AB0, Rhesus, P, Lewis, Kell, HP, GC, C′3, TF, 6PGD, GLO1, ESD, ACP, but not PGM1, systems were similar to the mean allele frequencies at these loci observed in the other ethnic groups from the Dagestan, Caucasus, and the whole European historical ethnographic province. At the same time, the allele frequency values obtained were different from those for the populations of Kazakhstan, Central Asia, Siberia, and the Ruswsian Far East. Thus, the results obtained for classical genetic markers indicate that Kumyks are genetically closer to the indigenous populations of Dagestan than to Turkic-speaking populations. Analysis of the fit of the observed phenotype frequencies to the Hardy-Weinberg expectations showed that compared to other indigenous populations of Dagestan examined, in Kumyks the genetic state of the population upon random allele association was close to equilibrium. Probably, this state was determined by practical absence of the consanguineous marriages upon preservation of intra-aul endogamy.  相似文献   

15.
Population contribution to genetic diversity can be estimated using neutral variation. However, population expansion or hybridization of diverged ancestries may weaken correlation between neutral and non-neutral variation. Microsatellite variation was studied at 25 loci in 20 native and 12 modern or imported northern European sheep breeds. Breed contributions to total gene diversity, allelic richness and mean allele-sharing distance between individuals were measured. Indications of changes in population size and admixtures of divergent ancestries were investigated and the extent of inbreeding was estimated. The northern European sheep demonstrated signs of reduction in effective population size. Many old, small populations made a substantial positive contribution to total molecular variation, but populations with several divergent major ancestries did not contribute substantially to molecular variation, with the exception of the Norwegian Rygja sheep. However, several diverged major ancestries may cause it to contribute less to non-neutral variation than expected from the microsatellite data. Breed uniqueness and within-breed variability generally had opposite effects on breed contributions to molecular diversity. The degree of inbreeding did not reflect the breed contribution to total gene diversity or allelic richness, but inbred populations increased the mean allele-sharing distance between individuals. Our study indicates breed conservation to be especially important in maintaining allelic variation in northern European sheep and supports the evolutionary importance of peripheral populations.  相似文献   

16.
Mitochondrial DNA D-loop (control) region (426-bp) was used to infer the genetic structure of Spanish mackerel (Scomberomorus commerson) from populations in Southeast Asia (Brunei, East and West Malaysia, Philippines, Thailand, Singapore, and China) and northern Australia (including western Timor). An east–west division along Wallace’s Line was strongly supported by a significant AMOVA, with 43% of the total sequence variation partitioned among groups of populations. Phylogenetic and network analyses supported two clades: clade A and clade B. Members of clade A were found in Southeast Asia and northern Australia, but not in locations to the west (Gulf of Thailand) or north (China). Clade B was found exclusively in Southeast Asia. Genetic division along Wallace’s Line suggests that co-management of S. commerson populations for future sustainability may not be necessary between Southeast Asian nations and Australia, however all countries should share the task of management of the species in Southeast Asia equally. More detailed genetic studies of S. commerson populations in the region are warranted.  相似文献   

17.
Small Tail Han (STH) sheep is a famous Chinese local breed and has perfect prolificacy performance, but it is inferior to imported mutton sheep breeds on meat production. In this study, six imported male sheep populations (White Suffolk, Black Suffolk, Texel, Dorper, South African Mutton Merino and East Friesian) were crossbred with STH female sheep respectively. The heterosis values of litter size, average daily gain (ADG) and feed conversion ratio (FCR) of crossbred sheep were analyzed for seeking the optimal cross. Meanwhile 28 microsatellite markers were used to measure the genetic distance between imported populations and STH population. Regression between the genetic distance and heterosis was analyzed for evaluating potential of microsatellite on predicting heterosis. Results showed a significant positive linear correlation (r = 0.892, P < 0.05) between heterosis of litter size and genetic distance D A of six crosses. This implied that these microsatellite markers had moderate potential to forecast heterosis of litter size in sheep. Results of this study also indicated that South African Mutton Merino and East Friesian sheep would be the optimal sire breeds for the litter size and might bring the greatest economic benefit in six imported populations; Suffolk sheep could be prior consideration as sire breeds when breeding objective focused on ADG. Finally these results provided valuable information for Chinese sheep industry.  相似文献   

18.
The prehistoric peopling of East Asia by modern humans remains controversial with respect to early population migrations. Here, we present a systematic sampling and genetic screening of an East Asian-specific Y-chromosome haplogroup (O3-M122) in 2,332 individuals from diverse East Asian populations. Our results indicate that the O3-M122 lineage is dominant in East Asian populations, with an average frequency of 44.3%. The microsatellite data show that the O3-M122 haplotypes in southern East Asia are more diverse than those in northern East Asia, suggesting a southern origin of the O3-M122 mutation. It was estimated that the early northward migration of the O3-M122 lineages in East Asia occurred approximately 25,000-30,000 years ago, consistent with the fossil records of modern humans in East Asia.  相似文献   

19.
Lu S  Chang H  Du L  Tsunoda K  Sun W  Yang Z  Chang G  Ji D 《Biochemical genetics》2005,43(5-6):251-260
Using the method of random sampling in typical colonies of the central area of the habitat and several electrophoresis techniques, the variations of 12 structural loci encoding blood protein of 60 Small-tailed Han sheep were examined and compared with those of four other sheep populations from coastal areas in East Asia to explore their phylogenetic relationships. Average heterozygosity of the five populations was: Kharkhorin sheep 0.3447, Ulaanbaatar sheep 0.3285, Small-tailed Han sheep 0.3157, Hu sheep 0.3884, and Cham Tribe sheep 0.2300. The earlier researchers' conclusion through documentary research, indicating that Small-tailed Han sheep and Hu sheep both evolved from Mongolian sheep, was further verified by the results of this study. Hu sheep, Small-tailed Han sheep, and Cham Tribe sheep were decreasingly affected by the bloodline of Mongolian sheep. A partial founder population, i.e., Mongolian sheep forming current Small-tailed Han sheep, possibly made a contribution to the bloodline of Cham Tribe sheep.  相似文献   

20.
The genetic variability of 204 sheep from nine breeds (Awassi, Çine Çapar?, Karaka?, Karya, Karayaka, Morkaraman, Norduz, Sak?z and Tuj) growing in four different regions (western, northern, eastern and south‐eastern Anatolia) was assessed using 18 microsatellite loci. High mean number of alleles, allelic richness and factorial correspondence analysis showed the degree of admixture between native sheep breeds of Turkey. The Karya and Çine Çapar? breeds were observed as the most distinct of the breeds, and possible introgressions were detected in other breeds. It was found that 8.9% of genetic variation resulted from the difference between the populations. The genetic variation in Turkish breeds was not much higher than that of European breeds, which might be a consequence of the recent sharp decrease in sheep numbers.  相似文献   

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