Frequencies of mitochondrial DNA haplotypes in laboratory cage populations of the mosquito, Aedes albopictus.

Abstract A laboratory cage experiment was undertaken to study changes over time in the frequencies of two mitochondrial DNA (mtDNA) haplotypes in the mosquito, Aedes albopictus, under two conditions: bidirectionally compatible matings and unidirectionally incompatible matings. Frequencies were monitored for 10 generations in three replicate cages for each of the two conditions above. In cages with bidirectionally compatible strains, changes in haplotype frequencies were nondirectional and neither haplotype increased in frequency. Statistical analysis of relative proportions of the two haplotypes in each generation indicated that the magnitude of the observed fluctuations could be expected under an assumption of random genetic drift alone. In cages with unidirectionally incompatible matings, mtDNA of females that lay inviable eggs upon mating with males of another strain, decreased significantly in the F1 generation and was completely replaced in the F2 generation.

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Plasma profiles of IL-6 and TNF with fever-inducing doses of lipopolysaccharide in dogs

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1990.259.1.r126 ◽

1990 ◽

Vol 259 (1) ◽

pp. R126-R132 ◽

Cited By ~ 6

Author(s):

D. R. LeMay ◽

L. G. LeMay ◽

M. J. Kluger ◽

L. G. D'Alecy

Keyword(s):

Statistical Analysis ◽

Tumor Necrosis Factor ◽

Interleukin 6 ◽

Tumor Necrosis ◽

Threshold Region ◽

Plasma Cytokine ◽

Changes Over Time ◽

Dose Dependent ◽

Necrosis Factor ◽

Over Time

This study was designed to test the tumor necrosis factor (TNF) WEHI 164 clone 13 bioassay and the interleukin 6 (IL-6) B9 bioassay for sensitivity to endogenously produced dog TNF and IL-6 and then to use these assays to examine the associations between these cytokines and lipopolysaccharide (LPS)-induced fever. When dogs were injected with LPS (40, 10, 1, 0.1, and 0.01 microgram/kg), the resulting fever was dose dependent. A plot of plasma cytokine changes over time following LPS injections showed that the plasma TNF-like activity appeared to increase in an all-or-none dose response, whereas the increase in plasma IL-6-like activity appeared to be log dose dependent. Plasma TNF-like and IL-6-like activity were then separately plotted against temperature change (fever). Statistical analysis supported the interpretation that both TNF-like and IL-6-like activity were related to LPS-fever in an all-or-none manner, with IL-6 having a threshold region. We conclude that if these cytokines are circulating mediators of fever, they may induce fever in an all-or-none fashion.

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Applications of Supercomputers in Population Genetics

Advances in Systems Analysis, Software Engineering, and High Performance Computing - Research and Applications in Global Supercomputing ◽

10.4018/978-1-4666-7461-5.ch007 ◽

2015 ◽

pp. 176-200

Author(s):

Gerard G. Dumancas

Keyword(s):

Population Genetics ◽

Natural Selection ◽

Genetic Drift ◽

Critical Role ◽

Allele Frequency Distribution ◽

Modern Approach ◽

Mathematical Discipline ◽

Modern Evolutionary Synthesis ◽

Changes Over Time ◽

Over Time

Population genetics is the study of the frequency and interaction of alleles and genes in population and how this allele frequency distribution changes over time as a result of evolutionary processes such as natural selection, genetic drift, and mutation. This field has become essential in the foundation of modern evolutionary synthesis. Traditionally regarded as a highly mathematical discipline, its modern approach comprises more than the theoretical, lab, and fieldwork. Supercomputers play a critical role in the success of this field and are discussed in this chapter.

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Sharing of heteroplasmies between human liver lobes varies across the mtDNA genome

10.1101/155796 ◽

2017 ◽

Author(s):

Alexander Hübner ◽

Manja Wachsmuth ◽

Roland Schröder ◽

Mingkun Li ◽

Anna Maria Eis-Hübinger ◽

...

Keyword(s):

Mitochondrial Dna ◽

Control Region ◽

Genetic Drift ◽

Human Liver ◽

Progenitor Cell ◽

Human Tissues ◽

Random Genetic Drift ◽

Coding Region ◽

Significant Excess ◽

Open Question

ABSTRACTMitochondrial DNA (mtDNA) heteroplasmy (intra-individual variation) varies among different human tissues and increases with age, suggesting that the majority of mtDNA heteroplasmies are acquired, rather than inherited. However, the extent to which heteroplasmic sites are shared across a tissue remains an open question. We therefore investigated heteroplasmy in two liver samples (one from each primary lobe) from 83 Europeans, sampled at autopsy. Minor allele frequencies (MAF) at heteroplasmic sites were significantly correlated between the two liver samples from an individual, with significantly more sharing of heteroplasmic sites in the control region than in the coding region. We show that this increased sharing for the control region cannot be explained by recent mutations at just a few specific heteroplasmic sites or by the possible presence of 7S DNA. Moreover, we carried out simulations to show that there is significantly more sharing than would be predicted from random genetic drift from a common progenitor cell. We also observe a significant excess of non-synonymous vs. synonymous heteroplasmies in the coding region, but significantly more sharing of synonymous heteroplasmies. These contrasting patterns for the control vs. the coding region, and for non-synonymous vs. synonymous heteroplasmies, suggest that selection plays a role in heteroplasmy sharing.

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The Distribution of Mitochondrial DNA Heteroplasmy Due to Random Genetic Drift

The American Journal of Human Genetics ◽

10.1016/j.ajhg.2008.10.007 ◽

2008 ◽

Vol 83 (5) ◽

pp. 582-593 ◽

Cited By ~ 50

Author(s):

Passorn Wonnapinij ◽

Patrick F. Chinnery ◽

David C. Samuels

Keyword(s):

Mitochondrial Dna ◽

Genetic Drift ◽

Random Genetic Drift ◽

Mitochondrial Dna Heteroplasmy

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Uneven Odds

10.1093/oso/9780199480142.001.0001 ◽

2018 ◽

Cited By ~ 3

Author(s):

Divya Vaid

Keyword(s):

Statistical Analysis ◽

Social Class ◽

Social Mobility ◽

Quantitative Methods ◽

National Level ◽

National Scale ◽

And Gender ◽

Anthropological Literature ◽

Changes Over Time ◽

Over Time

Focussing on patterns of intergenerational stability, this book traces the unequal structures of opportunity in India. The author addresses questions and approaches towards social mobility (or the lack thereof) through interactions between social class, caste, and gender while adopting a rural–urban perspective, capturing changes over time, and the implications of social mobility on a national scale. This book plugs in crucial gaps in the research on social mobility, which has been marked by the lack of precision regarding the extent of mobility in contemporary India. Using a broad lens of both caste and class, this up-to-date statistical analysis, which uses national-level datasets and advanced quantitative methods, enriches the sociological as well as the anthropological literature, while also locating India within the larger context of social mobility research in the industrialized and industrializing world.

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Evolution of single characters in the Jurassic ammonite Kosmoceras

Paleobiology ◽

10.1017/s0094837300003985 ◽

1981 ◽

Vol 7 (2) ◽

pp. 200-215 ◽

Cited By ~ 95

Author(s):

David M. Raup ◽

Rex E. Crick

Keyword(s):

Random Walk ◽

Natural Selection ◽

Temporal Variation ◽

Genetic Drift ◽

Null Hypothesis ◽

Morphological Characters ◽

Biological Interpretation ◽

Changes Over Time ◽

Biometrical Study ◽

Over Time

The classic biometrical study of phyletic evolution in Kosmoceras (Brinkmann 1929) is evaluated using unpublished raw data provided by Professor Brinkmann. Most morphological characters show statistically significant changes over time yet it is difficult to provide an unequivocal biological interpretation for these changes. In a few cases, runs tests indicate that evolution was nonrandom in the sense that fewer reversals in the direction of evolution occurred than would be predicted from a null hypothesis based on a random walk. These cases suggest persistence of natural selection regimes for fairly long periods of time. In other cases, and with other kinds of testing, the random walk model cannot be rejected although failure to reject the hypothesis does not justify its acceptance! Thus, the contribution of random factors (either genetic drift or selection in a randomly changing environment) cannot be assessed with confidence. It is problematical also whether the Kosmoceras series represent significant evolution by phyletic gradualism or just the natural temporal variation that characterizes stasis (sensu Eldredge and Gould 1972).

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Applications of Supercomputers in Population Genetics

Biotechnology ◽

10.4018/978-1-5225-8903-7.ch028 ◽

2019 ◽

pp. 693-719

Author(s):

Gerard G. Dumancas

Keyword(s):

Population Genetics ◽

Natural Selection ◽

Genetic Drift ◽

Critical Role ◽

Allele Frequency Distribution ◽

Modern Approach ◽

Mathematical Discipline ◽

Modern Evolutionary Synthesis ◽

Changes Over Time ◽

Over Time

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Random genetic drift in the female germline explains the rapid segregation of mammalian mitochondrial DNA

Nature Genetics ◽

10.1038/ng1096-146 ◽

1996 ◽

Vol 14 (2) ◽

pp. 146-151 ◽

Cited By ~ 385

Author(s):

Jack P. Jenuth ◽

Alan C. Peterson ◽

Katherine Fu ◽

Eric A. Shoubridge

Keyword(s):

Mitochondrial Dna ◽

Genetic Drift ◽

Random Genetic Drift ◽

Female Germline

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Comparison of two devices for measuring exercise transcutaneous oxygen pressures in patients with claudication

VASA ◽

10.1024/0301-1526/a000454 ◽

2015 ◽

Vol 44 (5) ◽

pp. 355-362 ◽

Cited By ~ 8

Author(s):

Marie Urban ◽

Alban Fouasson-Chailloux ◽

Isabelle Signolet ◽

Christophe Colas Ribas ◽

Mathieu Feuilloy ◽

...

Keyword(s):

Oxygen Pressure ◽

Optical Sensors ◽

Chemical Sensors ◽

Transcutaneous Oxygen ◽

Starting Values ◽

Two Systems ◽

Transcutaneous Oxygen Pressure ◽

New Sensors ◽

Changes Over Time ◽

Over Time

Abstract. Summary: Background: We aimed at estimating the agreement between the Medicap® (photo-optical) and Radiometer® (electro-chemical) sensors during exercise transcutaneous oxygen pressure (tcpO2) tests. Our hypothesis was that although absolute starting values (tcpO2rest: mean over 2 minutes) might be different, tcpO2-changes over time and the minimal value of the decrease from rest of oxygen pressure (DROPmin) results at exercise shall be concordant between the two systems. Patients and methods: Forty seven patients with arterial claudication (65 + / - 7 years) performed a treadmill test with 5 probes each of the electro-chemical and photo-optical devices simultaneously, one of each system on the chest, on each buttock and on each calf. Results: Seventeen Medicap® probes disconnected during the tests. tcpO2rest and DROPmin values were higher with Medicap® than with Radiometer®, by 13.7 + / - 17.1 mm Hg and 3.4 + / - 11.7 mm Hg, respectively. Despite the differences in absolute starting values, changes over time were similar between the two systems. The concordance between the two systems was approximately 70 % for classification of test results from DROPmin. Conclusions: Photo-optical sensors are promising alternatives to electro-chemical sensors for exercise oximetry, provided that miniaturisation and weight reduction of the new sensors are possible.

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