Population genetics of the people of Iran II. Genetic differentiation and population structure

1992 ◽  
Vol 7 (3) ◽  
pp. 11-18 ◽  
Author(s):  
S. S. Papiha ◽  
P. Amirshahi ◽  
E. Sunderland ◽  
D. D. Farhud ◽  
S. H. Tavakoli ◽  
...  
Keyword(s):  
Population Genetics ◽  
Population Structure ◽  
Genetic Differentiation ◽  
The People

scholarly journals Inherent population structure determines the importance of filtering parameters for reduced representation sequencing analyses

2020 ◽  
Author(s):  
D. Selechnik ◽  
M.F. Richardson ◽  
M.K. Hess ◽  
A.S. Hess ◽  
K.G. Dodds ◽  
...  
Keyword(s):  
Population Genetics ◽  
Population Structure ◽  
Genetic Differentiation ◽  
Call Rate ◽  
Wild Populations ◽  
Intrinsic Properties ◽  
Reduced Representation ◽  
Study Population ◽  
Low Levels ◽  
Reduced Representation Sequencing

AbstractAs technological advancements enhance our ability to study population genetics, we must understand how the intrinsic properties of our datasets influence the decisions we make when designing experiments. Filtering parameter thresholds, such as call rate and minimum minor allele frequency (MAF), are known to affect inferences of population structure in reduced representation sequencing (RRS) studies. However, it is unclear to what extent the impacts of these parameter choices vary across datasets. Here, we reviewed literature on filtering choices and levels of genetic differentiation across RRS studies on wild populations to highlight the diverse approaches that have been used. Next, we hypothesized that choices in filtering thresholds would have the greatest impact when analyzing datasets with low levels of genetic differentiation between populations. To test this hypothesis, we produced seven simulated RRS datasets with varying levels of population structure, and analyzed them using four different combinations of call rate and MAF. We performed the same analysis on two empirical RRS datasets (low or high population structure). Our simulated and empirical results suggest that the effects of filtering choices indeed vary based on inherent levels of differentiation: specifically, choosing stringent filtering choices was important to detect distinct populations that were slightly differentiated, but not those that were highly differentiated. As a result, experimental design and analysis choices need to consider attributes of each specific dataset. Based on our literature review and analyses, we recommend testing a range of filtering parameter choices, and presenting all results with clear justification for ultimate filtering decisions used in downstream analyses.

scholarly journals Development of microsatellite loci and population genetics in the bumblebee catfish species Pseudopimelodus atricaudus and Pseudopimelodus magnus (Siluriformes: Pseudopimelodidae)

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
José David Rangel-Medrano ◽  
Edna Judith Márquez
Keyword(s):  
Genetic Diversity ◽  
Population Genetics ◽  
Population Structure ◽  
Genetic Differentiation ◽  
River Basin ◽  
Microsatellite Loci ◽  
Population Genetic ◽  
High Genetic Diversity ◽  
The Family ◽  
The Mean

ABSTRACT The Neotropical freshwater catfish Pseudopimelodus atricaudus and Pseudopimelodus magnus are two recently discovered species endemic to the Colombian Magdalena-Cauca River basin. In this study, a set of 13 microsatellite loci were developed by using next generation sequence technology to assess the genetic diversity and population structure in P. atricaudus and test for cross-species amplification in P. magnus. Both species exhibited high genetic diversity (P. atricaudus: Na: 9.000 - 9.769 alleles/locus, Ho: 0.760 - 0.804, HE: 0.804 - 0.840; P. magnus: Na: 12.8 - 5.4 alleles/locus, Ho: 0.638 - 0.683, HE: 0.747 - 0.755) compared to the mean levels of genetic diversity reported for Neotropical Siluriformes, and lack of genetic differentiation among sampling sites within the Cauca River (P. atricaudus: F’ST=0.013 - 0.017, P > 0.05, D’est= -0.004 - 0.023, P > 0.05; P. magnus: F’ST= 0.031, P= 0.055; D’est= 0.045, P= 0.058). This work is the first insight on the diversity and the population genetics of species of the family Pseudopimelodidae and provides a framework to further population genetic and conservation analyses needed in this poorly studied family at the microevolutionary level.

scholarly journals Genetic Differentiation and Mixed Reproductive Strategies in the Northern Corn Leaf Blight Pathogen Setosphaeria turcica From Sweet Corn in Fujian Province, China

2021 ◽  
Vol 12 ◽  
Author(s):  
Yuli Dai ◽  
Lin Gan ◽  
Chengzhong Lan ◽  
Xuesong Lu ◽  
Xiujuan Yang ◽  
...  
Keyword(s):  
Population Genetics ◽  
Population Structure ◽  
Genetic Differentiation ◽  
Mating Type ◽  
Reproductive Strategies ◽  
Sweet Corn ◽  
Mating Types ◽  
Fujian Province ◽  
Northern Corn Leaf Blight ◽  
Corn Leaf Blight

The northern corn leaf blight (NCLB) pathogen Setosphaeria turcica (Luttrell) Leonard and Suggs is one of the main biotic constraints on sweet corn (Zea mays L.) yield and quality in Fujian Province, China. Currently, however, there is comparatively little information available regarding the distribution of mating types, population genetics, and reproductive strategies of this pathogen in Fujian. In this study, we investigated the distribution of mating types and population genetics of 117 isolates of S. turcica collected from seven of the main sweet corn-growing regions in Fujian Province, based on multiple polymerase chain reaction analyses using two mating type-specific primer pairs and 11 inter-simple sequence repeat markers. Furthermore, we examined the mode of reproduction of Fujian S. turcica populations. Both MAT1-1 and MAT1-2 mating types were detected throughout all seven sampling locations. The majority of MAT1-2 isolates were detected from Dongyou, Jian’ou, Pingnan, Songxi, and Longyan, whereas a large proportion of the detected MAT1-1 isolates were among those collected from Dongfeng and Nanjing. Furthermore, we detected five shared multi-locus haplotypes among S. turcica isolates from Dongyou, Jian’ou, Pingnan, Nanjing, and Songxi, whereas no shared haplotypes were observed between the Dongfeng (or Longyan) population and these five populations. Pairwise comparisons of the indices ΦPT and Nm, and population structure and principal coordinate analyses indicated genetic differentiation between both the regional and the mating type populations of S. turcica in Fujian. The skewed mating type ratio associated with low a haplotypic diversity and evident linkage disequilibrium reveals a mixed reproductive strategy for S. turcica populations in Fujian Province. The findings of this study advance our current understanding of the genetic diversity, population structure, and reproductive strategies of S. turcica populations infecting sweet corn in Fujian Province, and will potentially contribute to further resistance breeding efforts.

scholarly journals Comprehensive genotyping of a Brazilian cassava (Manihot esculenta Crantz) germplasm bank: insights into diversification and domestication

2021 ◽  
Vol 134 (5) ◽  
pp. 1343-1362
Author(s):  
Alex C. Ogbonna ◽  
Luciano Rogerio Braatz de Andrade ◽  
Lukas A. Mueller ◽  
Eder Jorge de Oliveira ◽  
Guillaume J. Bauchet
Keyword(s):  
Population Genetics ◽  
Population Structure ◽  
Manihot Esculenta ◽  
Ex Situ ◽  
Germplasm Bank ◽  
Effective Population ◽  
Manihot Esculenta Crantz ◽  
Genetic Groups ◽  
Population Structure Analysis ◽  
Modern Breeding

Abstract Key message Brazilian cassava diversity was characterized through population genetics and clustering approaches, highlighting contrasted genetic groups and spatial genetic differentiation. Abstract Cassava (Manihot esculenta Crantz) is a major staple root crop of the tropics, originating from the Amazonian region. In this study, 3354 cassava landraces and modern breeding lines from the Embrapa Cassava Germplasm Bank (CGB) were characterized. All individuals were subjected to genotyping-by-sequencing (GBS), identifying 27,045 single-nucleotide polymorphisms (SNPs). Identity-by-state and population structure analyses revealed a unique set of 1536 individuals and 10 distinct genetic groups with heterogeneous linkage disequilibrium (LD). On this basis, a density of 1300–4700 SNP markers were selected for large-effect quantitative trait loci (QTL) detection. Identified genetic groups were further characterized for population genetics parameters including minor allele frequency (MAF), observed heterozygosity $$({H}_{o})$$ ( H o ) , effective population size estimate $$\widehat{{(N}_{e}}$$ ( N e ^ ) and polymorphism information content (PIC). Selection footprints and introgressions of M. glaziovii were detected. Spatial population structure analysis revealed five ancestral populations related to distinct Brazilian ecoregions. Estimation of historical relationships among identified populations suggests an early population split from Amazonian to Atlantic forest and Caatinga ecoregions and active gene flows. This study provides a thorough genetic characterization of ex situ germplasm resources from cassava’s center of origin, South America, with results shedding light on Brazilian cassava characteristics and its biogeographical landscape. These findings support and facilitate the use of genetic resources in modern breeding programs including implementation of association mapping and genomic selection strategies.

scholarly journals BIOCHEMICAL GENETIC DIFFERENTIATION AMONG WILD POPULATIONS OF MILKFISH (Chanos chanos) IN INDONESIA

2017 ◽  
Vol 4 (1) ◽  
pp. 11
Author(s):  
Ketut Sugama ◽  
Agus Prijono
Keyword(s):  
Population Structure ◽  
Genetic Differentiation ◽  
Coastal Water ◽  
Wild Populations ◽  
Chanos Chanos ◽  
South Sulawesi ◽  
Biochemical Genetic

Four populations of milkfish (Chanos chanos ) were collected (N=100) from coastal water of  Aceh. Bali, East Java and South Sulawesi and were examined electrophoretically at 29 loci to deterurine the genetic vuriability and the population structure.

scholarly journals Genetic Diversity and Natural Selection of Plasmodium vivax Duffy Binding Protein-II From China-Myanmar Border of Yunnan Province, China

2021 ◽  
Vol 12 ◽  
Author(s):  
Tian-Qi Shi ◽  
Hai-Mo Shen ◽  
Shen-Bo Chen ◽  
Kokouvi Kassegne ◽  
Yan-Bing Cui ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Natural Selection ◽  
Genetic Differentiation ◽  
Positive Selection ◽  
Plasmodium Vivax ◽  
Yunnan Province ◽  
Duffy Binding Protein ◽  
Synonymous Mutations ◽  
Selection Of

Malaria incidence has declined dramatically over the past decade and China was certified malaria-free in 2021. However, the presence of malaria in border areas and the importation of cases of malaria parasites are major challenges for the consolidation of the achievements made by China. Plasmodium vivax Duffy binding protein (PvDBP) performs a significant role in erythrocyte invasion, and is considered a promising P. vivax vaccine. However, the highly polymorphic region of PvDBP (PvDBP-II) impedes the development of blood-stage vaccine against P. vivax. In this study, we investigated the genetic diversity and natural selection of PvDBP-II among 124 P. vivax isolates collected from the China-Myanmar border (CMB) in Yunnan Province, China, during 2009–2011. To compare genetic diversity, natural selection, and population structure with CMB isolates, 85 pvdbp-II sequences of eastern Myanmar isolates were obtained from GenBank. In addition, global sequences of pvdbp-II were retrieved from GenBank to establish genetic differentiation relationships and networks with the CMB isolates. In total, 22 single nucleotide polymorphisms reflected in 20 non-synonymous and two synonymous mutations were identified. The overall nucleotide diversity of PvDBP-II from the 124 CMB isolates was 0.0059 with 21 haplotypes identified (Hd = 0.91). The high ratio of non-synonymous to synonymous mutations suggests that PvDBP-II had evolved under positive selection. Population structure analysis of the CMB and eastern Myanmar isolates were optimally grouped into five sub-populations (K = 5). Polymorphisms of PvDBP-II display that CMB isolates were genetically diverse. Mutation, recombination, and positive selection promote polymorphism of PvDBP-II of P. vivax population. Although low-level genetic differentiation in eastern Myanmar was identified along with the more effective malaria control measures, the complexity of population structure in malaria parasites has maintained. In conclusion, findings from this study advance knowledge of the understanding of the dynamic of P. vivax population, which will contribute to guiding the rational design of a PvDBP-II based vaccine.

scholarly journals Population Genetics of the Red Rock Lobster,  Jasus edwardsii

2021 ◽  
Author(s):  
◽  
Luke Thomas
Keyword(s):  
Population Structure ◽  
Gene Flow ◽  
New Zealand ◽  
Genetic Differentiation ◽  
Microsatellite Markers ◽  
Rocky Reef ◽  
Rock Lobster ◽  
Wide Range ◽  
Jasus Edwardsii ◽  
Polymorphic Microsatellite

<p>Understanding patterns of gene flow across a species range is a vital component of an effective fisheries management strategy. The advent of highly polymorphic microsatellite markers has facilitated the detection of fine-scale patterns of genetic differentiation at levels below the resolving power of earlier techniques. This has triggered the wide-spread re-examination of population structure for a number of commercially targeted species. The aims of thesis were to re-investigate patterns of gene flow of the red rock lobster Jasus edwardsii throughout New Zealand and across the Tasman Sea using novel microsatellite markers. Jasus edwardsii is a keystone species of subtidal rocky reef system and supports lucrative export markets in both Australia and New Zealand. Eight highly polymorphic microsatellite markers were developed from 454 sequence data and screened across a Wellington south coast population to obtain basic diversity indices. All loci were polymorphic with the number of alleles per locus ranging from 6-39. Observed and expected heterozygosity ranged from 0.563-0.937 and 0.583-0.961, respectively. There were no significant deviations from Hardy-Weinberg equilibrium following standard Bonferroni corrections. The loci were used in a population analysis of J. edwardsii that spanned 10 degrees of latitude and stretched 3,500 km across the South Pacific. The analysis rejected the null-hypothesis of panmixia based on earlier mDNA analysis and revealed significant population structure (FST=0.011, RST=0.028) at a wide range of scales. Stewart Island was determined to have the highest levels of genetic differentiation of all populations sampled suggesting a high degree of reproductive isolation and self-recruitment. This study also identified high levels of asymmetric gene flow from Australia to New Zealand indicating a historical source-sink relationship between the two countries. Results from the genetic analysis were consistent with results from oceanographic dispersal models and it is likely that the genetic results reflect historical and contemporary patterns of Jasus edwardsii dispersal and recruitment throughout its range.</p>

scholarly journals Dynamic genetic diversity and population structure of Coreius guichenoti

ZooKeys ◽  
2021 ◽  
Vol 1055 ◽  
pp. 135-148
Author(s):  
Dongqi Liu ◽  
Feng Lan ◽  
Sicai Xie ◽  
Yi Diao ◽  
Yi Zheng ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Mitochondrial Dna ◽  
Population Structure ◽  
Genetic Differentiation ◽  
Yangtze River ◽  
Fish Passage ◽  
The Yangtze River ◽  
Artificial Breeding ◽  
Significant Difference ◽  
High Elevations

To investigate the genetic effects on the population of Coreius guichenoti of dam constructions in the upper reaches of the Yangtze River, we analyzed the genetic diversity and population structure of 12 populations collected in 2009 and 2019 using mitochondrial DNA (mtDNA) control regions. There was no significant difference in genetic diversity between 2009 and 2019 (P &gt; 0.05), but the population structure tended to become stronger. Genetic differentiation (FST) among five populations (LX, BB, YB, SF and JA) collected in 2009 was not significant (P &gt; 0.05). However, some populations collected in 2019 were significantly differentiated (P &lt; 0.05), indicating that the population structure has undergone change. A correlation analysis showed that the genetic diversity of the seven populations collected in 2019 was significantly negatively correlated with geographical height (r = −0.808, P = 0.028), indicating that the populations at high elevations were more vulnerable than those at low elevations. In order to prevent the further decrease of genetic diversity and population resources, some conservation and restoration suggestions, such as fish passage and artificial breeding, are put forward.

scholarly journals A differential expression of pyrethroid resistance genes in the malaria vector Anopheles funestus across Uganda is associated with patterns of gene flow

PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0240743
Author(s):  
Maurice Marcel Sandeu ◽  
Charles Mulamba ◽  
Gareth D. Weedall ◽  
Charles S. Wondji
Keyword(s):  
Population Structure ◽  
Gene Flow ◽  
Genetic Structure ◽  
Genetic Differentiation ◽  
Insecticide Resistance ◽  
Pyrethroid Resistance ◽  
Anopheles Funestus ◽  
Metabolic Resistance ◽  
Transcription Analysis ◽  
Genome Wide

Background Insecticide resistance is challenging the effectiveness of insecticide-based control interventions to reduce malaria burden in Africa. Understanding the molecular basis of insecticides resistance and patterns of gene flow in major malaria vectors such as Anopheles funestus are important steps for designing effective resistance management strategies. Here, we investigated the association between patterns of genetic structure and expression profiles of genes involved in the pyrethroid resistance in An. funestus across Uganda and neighboring Kenya. Methods Blood-fed mosquitoes An. funestus were collected across the four localities in Uganda and neighboring Kenya. A Microarray-based genome-wide transcription analysis was performed to identify the set of genes associated with permethrin resistance. 17 microsatellites markers were genotyped and used to establish patterns of genetic differentiation. Results Microarray-based genome-wide transcription profiling of pyrethroid resistance in four locations across Uganda (Arua, Bulambuli, Lira, and Tororo) and Kenya (Kisumu) revealed that resistance was mainly driven by metabolic resistance. The most commonly up-regulated genes in pyrethroid resistance mosquitoes include cytochrome P450s (CYP9K1, CYP6M7, CYP4H18, CYP4H17, CYP4C36). However, expression levels of key genes vary geographically such as the P450 CYP6M7 [Fold-change (FC) = 115.8 (Arua) vs 24.05 (Tororo) and 16.9 (Kisumu)]. In addition, several genes from other families were also over-expressed including Glutathione S-transferases (GSTs), carboxylesterases, trypsin, glycogenin, and nucleotide binding protein which probably contribute to insecticide resistance across Uganda and Kenya. Genotyping of 17 microsatellite loci in the five locations provided evidence that a geographical shift in the resistance mechanisms could be associated with patterns of population structure throughout East Africa. Genetic and population structure analyses indicated significant genetic differentiation between Arua and other localities (FST>0.03) and revealed a barrier to gene flow between Arua and other areas, possibly associated with Rift Valley. Conclusion The correlation between patterns of genetic structure and variation in gene expression could be used to inform future interventions especially as new insecticides are gradually introduced.

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