scholarly journals The genetic structure of admixed populations.

Genetics ◽  
1991 ◽  
Vol 127 (2) ◽  
pp. 417-428 ◽  
Author(s):  
J C Long
Keyword(s):  
Natural Selection ◽  
Genetic Structure ◽  
Genetic Drift ◽  
Hybrid Population ◽  
Fixation Index ◽  
Human Populations ◽  
Random Errors ◽  
Chi Square ◽  
Testing Procedures ◽  
Chi Square Test

Abstract A method for simultaneously estimating the admixture proportions of a hybrid population and Wright's fixation index, FST, for that hybrid is presented. It is shown that the variance of admixture estimates can be partitioned into two components: (1) due to sample size, and (2) due to evolutionary variance (i.e., genetic drift). A chi-square test used to detect heterogeneity of admixture estimates from different alleles, or loci, can now be corrected for both sources of random errors. Hence, its value for the detection of natural selection from heterogeneous admixture estimates is improved. The estimation and testing procedures described above are independent of the dynamics of the admixture process. However, when the admixture dynamics can be specified, FST can be predicted from genetic principles. Two admixture models are considered here, gene flow and intermixture. These models are of value because they lead to very different predictions regarding the accumulation of genes from the parental populations and the accumulation of variance due to genetic drift. When there is not evidence for natural selection, and it is appropriate to apply these models to data, the variance effective size (Ne) of the hybrid population can be estimated. Applications are made to three human populations: two of these are Afro-American populations and one is a Yanomamö Indian village. Natural selection could not be detected using the chi-square test in any of these populations. However, estimates of effective population sizes do lead to a richer description of the genetic structure of these populations.

scholarly journals Pesticides and the evolution of the genetic structure of Anopheles coluzzii populations in some localities in Benin (West Africa)

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Arsène Jacques Y. H. Fassinou ◽  
Come Z. Koukpo ◽  
Razaki A. Ossè ◽  
Fiacre R. Agossa ◽  
Roseric Azondékon ◽  
...  
Keyword(s):  
Genetic Structure ◽  
Genetic Differentiation ◽  
Anopheles Coluzzii ◽  
Natural Habitats ◽  
Chi Square ◽  
Agroecological Zones ◽  
Chi Square Test ◽  
Hardy Weinberg Equilibrium ◽  
Study Sites ◽  
Homozygous Resistant

Abstract Background Changes in the natural habitats of insect groups are determined the genetic polymorphisms between individuals. The objective of this study was to establish the genetic structure of the Anopheles coluzzii populations in four localities of Benin. Methods Insecticide surveys and larval sampling were conducted on 4 study localities, including Cotonou, Ketou, Zagnanado, and Sô-Ava. Molecular characterizations were performed on the Anopheles mosquitoes collected with the allelic and genotypic frequencies of kdr gene determined. The multiple comparison Chi square test for proportions was performed with R version 3.3.3. Next, the observed heterozygosity, expected heterozygosity, and indices of fixation, and genetic differentiation were estimated. Finally, the Hardy–Weinberg equilibrium (EHW) was determined to assess whether panmixia exists in the different populations of mosquitoes of the agroecological zones under study. Results Carbamates, pyrethroids, organophosphorus and organochlorines use have been reported in all localities except Sô-Ava. Anopheles coluzzii was strongly represented across all study localities. The L1014F allele was observed in the localities of Kétou, Cotonou and Zagnanado. Likewise, insecticide selection pressure of homozygous resistant individuals (L1014F/L1014F) was significantly higher in Kétou, Cotonou and Zagnanado (p value < 0.05). Surprisingly in Sô-Ava, a relatively high frequency of the L1014F allele despite the reported absence of pesticide use was observed. All mosquito populations were found to be deficient in heterozygosity across the study sites (FIS< 0). No genetic differentiation (FST< 0) was observed in the localities of Zagnanado and Kétou. Conclusion The survey on the use of insecticides showed that insecticide selection pressures differ across the investigated localities. It would be desirable to rotate or apply formulations of combined products with different modes of action. Doing so would enable a better management of resistant homozygous individuals, and mitigate the resistance effect of commonly used insecticides.

scholarly journals Sexual Recombination in the Botrytis cinerea Populations in Hungarian Vineyards

2008 ◽  
Vol 98 (12) ◽  
pp. 1312-1319 ◽  
Author(s):  
Kálmán Z. Váczy ◽  
Erzsébet Sándor ◽  
Levente Karaffa ◽  
Erzsébet Fekete ◽  
Éva Fekete ◽  
...  
Keyword(s):  
Botrytis Cinerea ◽  
Geographic Origin ◽  
Elongation Factor ◽  
Gray Mold ◽  
Fixation Index ◽  
Phylogenetic Species ◽  
Chi Square ◽  
Phylogenetic Resolution ◽  
Chi Square Test ◽  
Group Ii

Botrytis cinerea (anamorph of Botryotinia fuckeliana) causes gray mold on a high number of crop plants including grapes. In this study, we investigated the genetic properties of a grape pathogenic population of B. cinerea in the area of Eger, Hungary. A total of 109 isolates from 12 areas were sampled. Based on the sequence of the β-tubulin (tub1) locus, they all belong to group II, a phylogenetic species within B. cinerea. Seventy-four isolates were classified as transposa, with both the Flipper and Boty transposons, and 10 were classified as vacuma, lacking both transposons. The remaining isolates contained either only Flipper (13) or Boty (12). Multilocus analysis of sequences from tub1 and two other loci (elongation factor 1-alpha, tef1, and a minisatellite from the intron of an ATPase, MSB1) led to poor phylogenetic resolution of strains in individual clades. Analysis of five microsatellites (Bc2, Bc3, Bc5, Bc6, and Bc10) resulted in 55 microsatellite haplotypes within the 109 strains. No correlation was detected among individual haplotypes and the presence/absence of Flipper and/or Boty, the geographic origin, or the year of isolation. Application of the index of association, the chi-square test, and the phi test consistently indicated that the population of Hungarian isolates of B. cinerea undergoes sexual reproduction. However, the index of association test suggested the presence of some clonality, and the fixation index showed a low or occasionally moderate level of fixation in the Flipper populations. We conclude that the B. cinerea populations in Hungary consist of a strongly recombining group II phylogenetic species.

A STUDY USING DEMOGRAPHIC DATA OF GENETIC DRIFT AND NATURAL SELECTION IN AN ISOLATED MEDITERRANEAN COMMUNITY: BAYÁRCAL (LA ALPUJARRA, SOUTH-EAST SPAIN)

2011 ◽  
Vol 43 (4) ◽  
pp. 401-411
Author(s):  
F. LUNA ◽  
A. R. TARELHO ◽  
A. M. CAMARGO ◽  
V. ALONSO
Keyword(s):  
Natural Selection ◽  
Reproductive Isolation ◽  
Genetic Drift ◽  
Demographic Transition ◽  
Demographic Data ◽  
Human Populations ◽  
Native Population ◽  
Evolutionary Mechanisms ◽  
Developing Communities ◽  
Mediterranean Community

SummaryNatural selection and genetic drift are two evolutionary mechanisms that can be analysed in human populations using their fertility and mortality patterns, and their reproductive size and isolation, respectively. This paper analyses the models of natural selection and genetic drift in Bayárcal, south-east Spain, and compares them with the observed models in the rest of the Alpujarran region. Demographic data were obtained from a sample of 77 families (48.45% of the population, with 547 inhabitants). The genetic drift and natural selection action was evaluated with the Coefficient of Breeding Isolation (CBI of Lasker and Kaplan) and Crow's index, respectively. The CBI (23.23/12.61) suggests that genetic drift is near to acting, and Crow's index (I=0.58) is slightly higher than that observed in the rest of La Alpujarra. Although the reproductive isolation of Bayárcal is not effective enough for genetic drift to act, it is near when marital migrants inside the Bayárcal valley are considered as a native population. The natural selection pattern is not different from that of the rest of La Alpujarra, but it tends towards the model of developing communities, where the demographic transition has not yet begun.

scholarly journals The genetic structure of populations of orchids and its evolutionary importance: understanding processes from patterns

Lankesteriana ◽  
2016 ◽  
Vol 3 (2) ◽  
Author(s):  
Raymond L. Tremblay
Keyword(s):  
Gene Flow ◽  
Natural Selection ◽  
Genetic Structure ◽  
Population Size ◽  
Effective Population Size ◽  
Genetic Drift ◽  
Mating Systems ◽  
Mutation Rates ◽  
Effective Population ◽  
Genetic Structure Of Populations

<div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span>Evolution through either natural selection or genetic drift is dependent on variation at the genetic and mor- phological levels. Processes that influence the genetic structure of populations include mating systems, effective population size, mutation rates and gene flow among populations. </span></p></div></div></div>

scholarly journals Isoenzymatic variability in progeny of Pinus mugo Turra x Pinus sylvestris L. hybrids from Bór na Czerwonem, in experimental culture

2014 ◽  
Vol 69 (2) ◽  
pp. 137-144 ◽  
Author(s):  
Maria A. Bobowicz ◽  
Władysław Danielewicz
Keyword(s):  
Genetic Structure ◽  
Pinus Sylvestris ◽  
Genetic Similarity ◽  
Hybrid Population ◽  
Fixation Index ◽  
Pinus Mugo ◽  
Similarity Coefficients ◽  
Hybrid Swarm ◽  
Pure Species ◽  
Natural Hybrids

The article describes the genetic structure of 12-year old seedlings. They were grown in an experimental culture representing the progeny of natural hybrids of <em>Pinus mugo</em> Turra and <em>Pinus sylvestris</em> L. from the peatbog Bór na Czerwonem. The studies were carried out on seedlings, employing electrophoresis of enzymatic proteins from winter buds. Parallel isoenzymatic analyses were also conducted for trees of <em>P. mugo</em> Turra from Tatra Mountains and for <em>P. sylvestris</em> L. trees from Białowieża in order to determine similarities of the hybrids to the 'pure' species, thought to represent parental forms, and for natural hybrids from Bór na Czerwonem. The obtained electrophoretic patterns made the determination of genetic structure of the population possible, namely of the observed heterozygosity, expected heterozygosity, Wright's fixation index and coefficients of similarity according to Nei and Hedrick. Genetic distances between the populations were also estimated. The variability of 11 enzymatic loci demonstrated the highest level of variability in the population of hybrids. Coefficients of genetic differentiation (GST) and of gene flow, (Nm) suggested a close relationship of the hybrids to <em>P. mugo</em> which may indicate an introgressive type of the hybrid swarm, from which the studied trees originated. The analysis of genetic similarity coefficients, according to Nei and Hedrick, demonstrated also an extensive similarity of the two hybrid groups to <em>P. mugo</em>. However, upon analysis of individual enzymatic loci, some of them highly resembled <em>P. mugo</em> while others were similar to <em>P. sylvestris</em>. The closest genetic similarity was demonstrated for the group of hybrids from the peatbog and the respective of hybrides group from culture. The variable gene expression as well as asymmetric inheritance of isoenzymes provided additional evidence of the introgressive character of the studied trees from the hybrid population.

scholarly journals Differences in local population history at the finest level: the case of the Estonian population

2020 ◽  
Vol 28 (11) ◽  
pp. 1580-1591 ◽  
Author(s):  
Vasili Pankratov ◽  
Francesco Montinaro ◽  
Alena Kushniarevich ◽  
Georgi Hudjashov ◽  
Flora Jay ◽  
...  
Keyword(s):  
Natural Selection ◽  
Genetic Structure ◽  
Population Size ◽  
Effective Population Size ◽  
Local Population ◽  
Population History ◽  
Human Populations ◽  
Effective Population ◽  
The Impact ◽  
Estonian Population

Abstract Several recent studies detected fine-scale genetic structure in human populations. Hence, groups conventionally treated as single populations harbour significant variation in terms of allele frequencies and patterns of haplotype sharing. It has been shown that these findings should be considered when performing studies of genetic associations and natural selection, especially when dealing with polygenic phenotypes. However, there is little understanding of the practical effects of such genetic structure on demography reconstructions and selection scans when focusing on recent population history. Here we tested the impact of population structure on such inferences using high-coverage (~30×) genome sequences of 2305 Estonians. We show that different regions of Estonia differ in both effective population size dynamics and signatures of natural selection. By analyzing identity-by-descent segments we also reveal that some Estonian regions exhibit evidence of a bottleneck 10–15 generations ago reflecting sequential episodes of wars, plague and famine, although this signal is virtually undetected when treating Estonia as a single population. Besides that, we provide a framework for relating effective population size estimated from genetic data to actual census size and validate it on the Estonian population. This approach may be widely used both to cross-check estimates based on historical sources as well as to get insight into times and/or regions with no other information available. Our results suggest that the history of human populations within the last few millennia can be highly region specific and cannot be properly studied without taking local genetic structure into account.

Hubungan Antara Menyusui Dengan Involusi Uterus Pada Ibu Nifas Fisiologis Di RSIA Aura Syifa Kabupaten Kediri

1970 ◽  
Vol 5 (2) ◽  
pp. 64
Author(s):  
Eny Sendra ◽  
Dewi Indriani
Keyword(s):  
Breast Feeding ◽  
Sampling Technique ◽  
Chi Square ◽  
Cross Sectional ◽  
Fisher Test ◽  
Key Word ◽  
Chi Square Test ◽  
The Moment

Breast feeding is giving milk to be drunk to the baby from the breast. Uterus involution is a process how the uterus return to the condition back, before pregnanting after bearing. At the moment of suckling, happens a stimulus and brings the hormones out, such as oksitosin uses not only to stimulate some muscles constraction but also to stimulate the uterus, so that the process of uterus involution happens foster. According to the explanations above, the research aimed to know about the correlation between breast feeding and uterus involution. This research’s design was, cross sectional by the population of all childbirth mothers approximately 50 persons / month. By using accidental sampling technique we got 21 sample respondents. The place of research in RSIA Aura Syifa in Kediri Regency on 16th until 22nd of June 2009. From this research’s result, we got 14 persons (66,67%) with normal uterus involution, suckled in a good way, one person (4,67%) with normal uterus involution, suckled in a wrong way, 2 persons (9,52%) with abnormal uterus involution, suckled in a good way and 4 persons (19,05%) with abnormal uterus involution, suckled in a wrong way. Statistic test which used chi-square test, counted the probability frequency in advance, from that we got 3 columns with the score, less than 5, so that chi-square can not be continued and by doing exact fisher test, the score was 0,001. Because P with the grade mistake 0,05 smaller, so the conclusion was “Ho” is rejected, it meant “there was correlation between suckling and uterus involution”. Key Word : Breast feeding, uterus involution

FAKTOR PERSONAL YANG BERHUBUNGAN DENGAN KOMITMEN ORGANISASI PERAWAT RSUD EMBUNG FATIMAH BATAM

2020 ◽  
Vol 5 (3) ◽  
pp. 875
Author(s):  
Asfri Sri Rahmadeni
Keyword(s):  
Organizational Commitment ◽  
Turnover Rate ◽  
Sampling Technique ◽  
Hospital Nurses ◽  
Test Results ◽  
Personal Factors ◽  
High Turnover ◽  
Chi Square ◽  
Cross Sectional ◽  
Chi Square Test

<p class="Normal1"><em>Commitment is the attitude or behavior of likes or dislikes shown by someone against the organization at work. Indonesia is recorded as a nurse who has a low organizational commitment (76%) so it harms services. This phenomenon in the hospital can be seen from the indicator of the high turnover rate of nurses which reaches 30.9% which exceeds the standard &lt;5%. Many factors affect organizational commitment. The purpose of this study was to analyze the Personal Factors Associated with Organizational Commitment of Hospital Nurses. This study is a cross-sectional analytic study and purposive sampling technique with a sample of 59 nurses. Chi-Square test results obtained personal factors that have a relationship with organizational commitment Nurse Hospital is age with p = 0,000 and education with p = 0,000, personal factors not related to organizational commitment are gender p = 1,053 and years of service with p = 1,147. Hospitals should conduct research/surveys on Organizational Commitment periodically as an evaluation material in the context of the organization's development and development in the future</em>.</p>

GAMBARAN INDEKS LARVA AEDES AEGYPTI DI BUFFER WILAYAH KERJA BANDARA SEPINGGAN BALIKPAPAN

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Abdurrakhman abdurrakhman Abdurrakhman
Keyword(s):  
Aedes Aegypti ◽  
Buffer Zone ◽  
Chi Square ◽  
Cross Sectional ◽  
Breeding Sites ◽  
Dengue Disease ◽  
Vector Borne Diseases ◽  
Transportation Equipment ◽  
Chi Square Test ◽  
Larvae Density

ABSTRACT : The House index and Container Index in the buffer area of ​​the working area of ​​Balikpapan Sepinggan Airport is still above 1%, so the potential for the spread of dengue disease. Mobilization of people, goods and transportation equipment will increasingly affect the transmission of disease in ports and airports, especially for vector-borne diseases. This study aims to analyze the risk factors associated with larvae density of Aedes aegypti and describe the larvae index in the buffer zone of the Sepinggan Balikpapan Airport This study was a descriptive study with a cross sectional design. The sample in this study was 121 houses with a proportionate stratified random sampling, the research location was in the buffer zone of Sepinggan Balikpapan Airport in November 2018. The variables studied were houses with positive larvae containers, breeding sites and PSN behavior and larvasidation. The data was analyzed using the chi square test. There was a relationship between houses with larvae positive Aedes aegypti, behavior of Mosquito Nest Eradication (PSN) and larvasidation with larvae density of Aedes aegypti but not for breeding sites (p = 0.00 and 95% CI = 0.64), and   (p = 0.00 and 95% CI = 0.34). The description of several Aedes aegypti larvae index, namely House Index (HI) = 57.02%, Container Index (CI) = 24.36%, Bruteau Index (BI) = 148.76, and Flick Free Numbers (ABJ) = 42.98 %. Houses with larvae of Aedes aegypti larvae and PSN and larvasidation behavior were associated with larvae density of Aedes aegypti. The index of HI, CI and BI larvae is of high value so there is a risk of DBD transmission

The Influence of Age and Gender on Mandibular Indices among the Libyan Population

2019 ◽  
Vol 3 (2) ◽  
Keyword(s):  
Negative Correlation ◽  
Bone Mineralization ◽  
Age Groups ◽  
T Test ◽  
Chi Square ◽  
Age And Gender ◽  
Significant Difference ◽  
Chi Square Test ◽  
And Gender ◽  
Libyan Population

Radiographic Mandibular Indices serve as easy and relatively cheap tools for evaluating bone mineralization. Objectives: To examine the effect of age and gender on three mandibular indices: the panoramic mandibular index (PMI), the mandibular ratio (MR) and the mandibular cortical index (MCI), among Libyan population. Methods: The three indices were measured on 317 digital (OPGs) of adult humans (155 males, 162 females). The sample was divided into six age groups (from 18-25 years through 56-65 years). The measurements were analyzed for interactions with age and sex, using SPSS (Statistical Package for Social Studies) software version no. 22. The tests employed were two way ANOVA, the unpaired T-test and chi-square test. Results: The mean PMI fluctuated between 0.37 s.d. 0.012 and 0.38 s.d. 0.012. among the sixth age groups. One-way ANOVA statistical test revealed no significant of age on PMI. On the other hand gender variation has effect on PMI, since independent sample t-test disclosed that the difference between the male and female PMI means statistically significant. ANOVA test showed that the means of MR among age groups showed a negative correlation i.e. MR mean declined from 3.01 in 18-25 age groups to 2.7 in 55-65 age groups. In contrary, the gender showed no effect on MR according two sample t-test at p> 0.05. In regards with MCI, statistical analysis showed that it affected by age that is C1 was decreasing by age while C2 and C3 were increased by age. Using chi square test the result indicated that there is a significant difference among the different age group and the two genders in MCI readings. Conclusion: PMI was influenced significantly by age but minimally by the gender. MR is not affected by gender but has a negative correlation with age. MCI is affected by both age and gender

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