Faculty Opinions recommendation of Independent introduction of two lactase-persistence alleles into human populations reflects different history of adaptation to milk culture.

Lactase persistence has long been recognized as a striking example of human dietary adaptation to changes in food production habits. The observation that the prevalence of lactase persistence is positively correlated with the cultural history of dairying in human populations has led to the formulation of an evolutionary interpretation that became known as the culture-historical hypothesis. This hypothesis emphasizes the influence that culturally derived selection can have on human genes by assuming that the nutritional benefits of milk drinking during adult life are selectively advantageous in groups that rely on dairying to subsist. The recent demonstration of the molecular basis of lactase persistence provided a unique opportunity to test the basic predictions of the culture-historical hypothesis and to evaluate its merit relative to alternative explanations. Here, I present an overview of the evolutionary history of lactase persistence by focusing on the predictions of the culture-historical hypothesis, including the correlation between lactase persistence and pastoralism, the age of lactase persistence mutations and molecular evidences for natural selection. The places of origin and geographic diffusion of lactase persistence mutations are also discussed in the context of the population movements associated with the spread of pastoralism.

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Humans: Evolution and Environment: C06 - History of Human populations, palaeoecology and ancient DNA, C08 - Bioarchaeology from the Midst of Shells, C14 - Modern Humans origins in Eurasia, C62 - Coastal geoarchaeology: the research of shellmounds, WS32 -

10.30861/9781407306032 ◽

2009 ◽

Keyword(s):

Ancient Dna ◽

Human Populations ◽

Modern Humans ◽

History Of

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Prevalence of Antimicrobial Resistant Bacteria from Conjunctival Flora in an Eye Infection Prone Breed (Saint Bernard)

Molecules ◽

10.3390/molecules26082219 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2219

Author(s):

George Cosmin Nadăș ◽

Cristiana Ștefania Novac ◽

Ioana Adriana Matei ◽

Cosmina Maria Bouari ◽

Zoltan Miklos Gal ◽

...

Keyword(s):

Multidrug Resistant ◽

Ocular Disease ◽

Resistant Bacteria ◽

Human Populations ◽

Disease Treatment ◽

Pseudomonas Spp ◽

History Of ◽

External Sources ◽

Staphylococcus Spp ◽

Saint Bernard

The conjunctival bacterial resident and opportunistic flora of dogs may represent a major source of dissemination of pathogens throughout the environment or to other animals and humans. Nevertheless, contamination with bacteria from external sources is common. In this context, the study of the antimicrobial resistance (AMR) pattern may represent an indicator of multidrug resistant (MDR) strains exchange. The present study was focused on a single predisposed breed—Saint Bernard. The evaluated animals were healthy, but about half had a history of ocular disease/treatment. The swabs collected from conjunctival sacs were evaluated by conventional microbiological cultivation and antimicrobial susceptibility testing (AST). The most prevalent Gram-positive was Staphylococcus spp.; regardless of the history, while Gram-negative was Pseudomonas spp.; exclusively from dogs with a history of ocular disease/treatment. Other identified genera were represented by Bacillus, Streptococcus, Trueperella, Aeromonas and Neisseria. The obtained results suggest a possible association between the presence of mixed flora and a history of ocular disease/treatment. A high AMR was generally observed (90%) in all isolates, especially for kanamycin, doxycycline, chloramphenicol and penicillin. MDR was recorded in Staphylococcus spp. and Pseudomonas spp. This result together with a well-known zoonotic potential may suggest an exchange of these strains within animal human populations and the environment.

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Sequence variation and evolution of nuclear DNA in man and the primates

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1981.0021 ◽

1981 ◽

Vol 292 (1057) ◽

pp. 133-142 ◽

Cited By ~ 5

Keyword(s):

Dna Sequence ◽

Sequence Variation ◽

Nuclear Dna ◽

Sequence Divergence ◽

Gene Arrangement ◽

Human Populations ◽

Genetic Changes ◽

Detailed Structural Analysis ◽

Dna Sequence Variation ◽

History Of

Recent advances in nucleic acid technology have facilitated the detection and detailed structural analysis of a wide variety of genes in higher organisms, including those in man. This in turn has opened the way to an examination of the evolution of structural genes and their surrounding and intervening sequences. In a study of the evolution of haemoglobin genes and neighbouring sequences in man and the primates, we have investigated gene arrangement and DNA sequence divergence both within and between species ranging from Old World monkeys to man. This analysis is beginning to reveal the evolutionary constraints that have acted on this region of the genome during primate evolution. Furthermore, DNA sequence variation, both within and between species, provides, in principle, a novel and powerful method for determining inter-specific phylogenetic distances and also for analysing the structure of present-day human populations. Application of this new branch of molecular biology to other areas of the human genome should prove important in unravelling the history of genetic changes that have occurred during the evolution of man.

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2000 Fleming Lecture. The origin and evolution of hepatitis viruses in humans

Journal of General Virology ◽

10.1099/0022-1317-82-4-693 ◽

2001 ◽

Vol 82 (4) ◽

pp. 693-712 ◽

Cited By ~ 150

Author(s):

Peter Simmonds

Keyword(s):

Large Population ◽

Human Populations ◽

Hepatitis Viruses ◽

Hepatitis G Virus ◽

Origin And Evolution ◽

Wide Range ◽

Population Sizes ◽

History Of ◽

Virus C ◽

Time Of Divergence

The spread and origins of hepatitis C virus (HCV) in human populations have been the subject of extensive investigations, not least because of the importance this information would provide in predicting clinical outcomes and controlling spread of HCV in the future. However, in the absence of historical and archaeological records of infection, the evolution of HCV and other human hepatitis viruses can only be inferred indirectly from their epidemiology and by genetic analysis of contemporary virus populations. Some information on the history of the latter may be obtained by dating the time of divergence of various genotypes of HCV, hepatitis B virus (HBV) and the non-pathogenic hepatitis G virus (HGV)/GB virus-C (GBV-C). However, the relatively recent times predicted for the origin of these viruses fit poorly with their epidemiological distributions and the recent evidence for species-associated variants of HBV and HGV/GBV-C in a wide range of non-human primates. The apparent conservatism of viruses over long periods implied by these latter observations may be the result of constraints on sequence change peculiar to viruses with single-stranded genomes, or with overlapping reading frames. Large population sizes and intense selection pressures that optimize fitness may be the factors that set virus evolution apart from that of their hosts.

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Patterns of smallpox mortality in London, England, over three centuries

PLoS Biology ◽

10.1371/journal.pbio.3000506 ◽

2020 ◽

Vol 18 (12) ◽

pp. e3000506

Author(s):

Olga Krylova ◽

David J. D. Earn

Keyword(s):

Public Health ◽

Infectious Disease ◽

Time Series ◽

Spectral Analysis ◽

Infectious Diseases ◽

Health Policies ◽

Human Populations ◽

Public Health Policies ◽

History Of ◽

History Of Control

Smallpox is unique among infectious diseases in the degree to which it devastated human populations, its long history of control interventions, and the fact that it has been successfully eradicated. Mortality from smallpox in London, England was carefully documented, weekly, for nearly 300 years, providing a rare and valuable source for the study of ecology and evolution of infectious disease. We describe and analyze smallpox mortality in London from 1664 to 1930. We digitized the weekly records published in the London Bills of Mortality (LBoM) and the Registrar General’s Weekly Returns (RGWRs). We annotated the resulting time series with a sequence of historical events that might have influenced smallpox dynamics in London. We present a spectral analysis that reveals how periodicities in reported smallpox mortality changed over decades and centuries; many of these changes in epidemic patterns are correlated with changes in control interventions and public health policies. We also examine how the seasonality of reported smallpox mortality changed from the 17th to 20th centuries in London.

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