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Epistasis refers to the influence of one genomic mutation or variant on the phenotypic effects of another mutation or variant.  Based on available evidence and theory, this phenomenon has a major influence on evolutionary trajectories for organisms of all sorts.  The role of epistasis has been studied primarily in the context of adaptive evolutionary change.  In a recent paper (2014), Gong and Bloom attempt to determine the relative frequencies of epistatic interactions in adaptive versus stochastic evolution, i.e. evolution driven by selection as opposed to evolution resulting from random processes without a significant selective ‘pressure.’  Gong and Bloom perform this comparison by analyzing homologous nucleoprotein (NP) genes in human and swine influenza A viruses.  The authors argue that the human viruses are subject to substantially more intense selection than the swine viruses since domestic swine are much shorter lived and their viruses are not as likely to be subjected to immune memory responses. Continue Reading »

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The evolutionary paradox and the missing heritability of schizophrenia
by van Dongen, J., & Boomsma, D. I. (2013).
American Journal of Medical Genetics Part B: Neuropsychiatric Genetics, 162(2), 122-136.
doi: 10.1002/ajmg.b.32135

Schizophrenia is one of the most detrimental common psychiatric disorders, occurring at a prevalence of approximately 1%, and characterized by increased mortality and reduced reproduction, especially in men. The heritability has been estimated around 70% and the genome-wide association meta-analyses conducted by the Psychiatric Genomics Consortium have been successful at identifying an increasing number of risk loci. Various theories have been proposed to explain why genetic variants that predispose to schizophrenia persist in the population, despite the fitness reduction in affected individuals, a question known as the evolutionary paradox. In this review, we consider evolutionary perspectives of schizophrenia and of the empirical evidence that may support these perspectives. Continue Reading »

An iTunes version of the course by Steve Stearns is now available free online, with vast supplementary material that is not available in the YouTube version.    To subscribe, launch the course on iTunes, or go to this site

 

Course Description Continue Reading »

After almost two years as an unofficial medical student interest group the Evolutionary Medicine Group at the Louisiana State University  School of Medicine in New Orleans  has gained official recognition by the institution.  If you know of other groups of medical students who are meeting to talk about evolutionary medicine, please add information as a comment below so we can establish a network of such groups.

The LSU group was started by first year medical students last year, with minimal faculty support, and continued to meet and recruit underclassmen throughout the current academic year. Participants will now receive credit hours towards the school’s “professional development” elective. The group follows a journal club style, with the presenting student choosing journal articles and leading discussion relevant to the month’s topic. Topics have included: Cancer Evolution in Human Microenvironments, Foundations of Evolution in Relation to Medicine, Evolution and Embryological Development, Infectious Disease Evolution, Current Environmental Mismatch with Evolved Human Traits, Evolutionary Basis of Aging, Epigenetics in Human Evolution, Evolution and Psychology, Using Evolution to Predict Outcomes of Medical Intervention, and The Human Microbiome. It is the hope that this group will increase the understanding of scientific literature, encourage peer-to-peer teaching, and lead to the development of evolutionary thinking in a new generation of physicians.

Any questions/comments can be directed to: Michelle Blyth (mblyth@lsuhsc.edu), Rebecca Kreston (rkrest@lsuhsc.edu) (student leaders) or Jason Mussell (jmusse@lsuhsc.edu), Hamilton Farris (hfarri@lsuhsc.edu) (faculty advisors)

45 lectures from the Yale Evolutionary Medicine course taught by Stephen Stearns are now available online, open access on a special You Tube channel.

This is a complete course, with high production values,  by a world leader in the field.

The lecture segments are 6 to 26 minutes in length, well suited to insertion into lectures or to assigning as a part of a course.

The placenta was long thought to be sterile, but a new study finds nucleic acid signatures of multiple species in a pattern similar to that in the oral cavity.

PlacentalMicrobiome
PlacentalMicrobiome

K. Aagaard, J. Ma, K. M. Antony, R. Ganu, J. Petrosino, J. Versalovic, The Placenta Harbors a Unique Microbiome. Sci. Transl. Med. 6, 237ra65 (2014).

A report in Nature by Katia Moskvitch is open access. 

The research report in Sci Trans Med is not open access, but the abstract is below.

Humans and their microbiomes have coevolved as a physiologic community composed of distinct body site niches with metabolic and antigenic diversity. The placental microbiome has not been robustly interrogated, despite recent demonstrations of intracellular bacteria with diverse metabolic and immune regulatory functions. A population-based cohort of placental specimens collected under sterile conditions from 320 subjects with extensive clinical data was established for comparative 16Sribosomal DNA–based and whole-genome shotgun (WGS) metagenomic studies. Identified taxa and their gene carriage patterns were compared to other human body site niches, including the oral, skin, airway (nasal), vaginal, and gut microbiomes from nonpregnant controls. We characterized a unique placental microbiome niche, composed of nonpathogenic commensal microbiota from the Firmicutes, Tenericutes, Proteobacteria, Bacteroidetes, and Fusobacteria phyla. In aggregate, the placental microbiome profiles were most akin (Bray-Curtis dissimilarity <0.3) to the human oral microbiome. 16S-based operational taxonomic unit analyses revealed associations of the placental microbiome with a remote history of antenatal infection (permutational multivariate analysis of variance, P = 0.006), such as urinary tract infection in the first trimester, as well as with preterm birth <37 weeks (P = 0.001).

An innovative format, Clinical Briefs cover crucial topics in just a page. They are available as html, or pdf format. All are open access.  See below and here for the first few published.

  1. Editorial

    • Gillian Bentley

    Editorial

    • Elspeth V. Best and
    • Mark D. Schwartz

    Fever Continue Reading »

The mathematician versus the malignancy

An engaging story about using mathematical models to improve chemotherapy.

 By Elie Dolgin

Nature Medicine 20, 460–463 (2014) doi:10.1038/nm0514-460 (open access)

The way in which people receive cancer therapy is pretty much the same as it’s been for decades: researchers determine the highest dose of a drug or treatment that does not cause unacceptable side effects; oncologists then administer that dose to patients on a standard timetable—usually daily tablets for oral chemotherapeutics and other pill-based regimens, infusions on a weekly schedule for injectable drugs and Monday-through-Friday treatments for radiation therapy.

Almost all current cancer therapies are given this way. And although the approach has undoubtedly extended countless patients’ lives, given that more than $80 billion is spent on cancer care in the US alone, it’s worth asking: are these schedules really yielding the best results for patients? And could alternative timetables produce better outcomes?

Franziska Michor hopes to answer these questions. Read more here

A report from the American Academy of Microbiology that is clear, short and engaging, and open access.

Executive Summary

Do you think the oncologists at a cutting-edge research hospital ever sit down with local farmers? Do you think the pharmaceutical researchers developing the next generation of anti-HIV drugs spend any time with the plant scientists working on the next generation of Roundup Ready soybeans?

If your answer to both questions is no, you would be mostly right. Even though all of these people are dealing with exactly the same evolutionary phenomena, they do not recognize themselves as a single scientific community and rarely get a chance to learn from each other. What they all have in common is that they are trying to eliminate an unwanted living entity – a cancer cell, a weed, a virus, an insect pest – but the treatments they develop eventually lose effectiveness because the target evolves resistance.

The emergence of resistance is a phenomenon with ancient evolutionary roots, Continue Reading »

Spermatogonial stem cells replicate and produce sperm throughout adult life, while oocyte precursors complete all of their mitotic cell divisions during fetal development and primary oocytes are arrested in meiosis at birth. Because many more rounds of cell division occur in spermatogenesis than in oogenesis, the incidence of germline mutations, and particularly of single base substitutions, is higher in sperm than in ova (Crow, 2000). Most single base substitutions occur roughly four or five times more frequently in sperm than in eggs, and the incidence of these mutations increases modestly with paternal age. Against this background, a handful of diseases, known as paternal age effect (PAE) diseases, stand out. PAE diseases, of which achondroplasia is the most common and best known, have several unusual features. Almost all (more than 95%) of the new mutations that cause these diseases occur in sperm; the incidence of these diseases increases significantly with paternal age, such that the fathers of affected patients are on average several years older than the fathers of unaffected babies in the same populations; and the genes underlying these diseases have unusually high apparent mutation rates. The mutations that cause PAE diseases are dominant, gain of function mutations in genes related to the RAS signal transduction pathway. Achondroplasia is due to mutations in fibroblast growth factor receptor 3 gene (FGFR3), while Costello syndrome, another PAE disease, is caused by mutations in the HRAS proto-oncogene. Continue Reading »

John W. Pepper, Barbara K. Dunn, Richard M. Fagerstrom, John K. Gohagan, and Nadarajen A. Vydelingum, “Using Systems Biology to Understand Cancer as an Evolutionary Process,” Journal of Evolutionary Medicine, vol. 2, Article ID 235678, 8 pages, 2014. doi:10.4303/jem/235678  (Open Access)

Abstract:  Unsatisfactory progress in cancer medicine and prevention calls for new research approaches. Research can broaden its view of cancer to include not only specific molecular elements, but also the process that explains their origin and dynamics. This process is Darwinian evolution of somatic cells. Applicable modeling techniques are available from process-oriented systems biology. We review relevant concepts and techniques, and their application to four key open questions in cancer prevention research. Helpful concepts are transferable from classical evolutionary biology and ecology, while useful techniques include computational agent-based modeling. The research questions we review include (1) why do benign neoplasms often progress to malignancy? (2) what is the chronological sequence of molecular events in cancer progression? (3) how can we find reliable molecular biomarkers for cancer? and (4) will evolved drug resistance stymie efforts at a long-term cancer chemoprevention? We conclude that molecular analysis can be usefully augmented with process-oriented systems biology to guide empirical research into the most productive directio

The Foundation for Evolution, Medicine, & Public Health announces the winner of the Omenn Prize for the best article published in 2013 on a topic related to evolution in the context of medicine and public health.  The Prize Committee, Allen Rodrigo (chair), Carl Bergstrom, and Sarah Tishkoff, considered 47 articles, and awarded the prize to Dual Host-Virus Arms Races Shape an Essential Housekeeping Protein by Demogines A, Abraham J, Choe H, Farzan M, Sawyer SL (2013). PLoS Biol 11(5):e1001571. doi: 10.1371/journal.pbio.1001571

The first author, Ann Demogines, will receive the $5000 Prize.  She is a Research Associate in the Center for Systems and Synthetic Biology, College of Natural Sciences, University of Texas, Austin, where she works in the laboratory of Sara Sawyer.  The Foundation is grateful to Gilbert Omenn for making this prize possible.

 The Committee cited four other papers for Honorable Mention:

The Prize Committee’s Award Statement Is below Continue Reading »

A prion is a protein that can adopt a conformation other than the ‘standard’ functional conformation and this alternative conformation favors self-association. The aggregation-associated conformation can then be imposed on additional copies of the protein in the original conformation.  This self-templating mechanism for propagation is known primarily for causing neurodegenerative conditions in humans and in animals, such as kuru or Creutzfeldt-Jakob disease in humans or bovine spongiform encephalopathy (i.e., mad cow disease) in cattle.  Since this process of converting protein conformations can be transmitted from one animal to another or one person to another by some routes, such as cannibalism in the case of kuru, the name prion was created to indicate an infectious protein particle.  This concept of an infectious agent that involved no nucleic acid was the basis for the Nobel Prize in Physiology or Medicine awarded to Stanley Prusiner in 1997 (http://www.nobelprize.org/nobel_prizes/medicine/laureates/1997/press.html). Continue Reading »

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Troubled sleep: Night waking, breastfeeding and parent–offspring conflict

A target article in Evolution, Medicine, and Public Health by David Haig on why infants cry at night, has  accompanying responses from Jim McKenna, Katie Hinde, Bernie Crespi, Patrick McNamara, and Jon Wilkins.  Open access

Abstract: Disrupted sleep is probably the most common complaint of parents with a new baby. Night waking increases in the second half of the first year of infant life and is more pronounced for breastfed infants. Sleep-related phenotypes of infants with Prader-Willi and Angelman syndromes suggest that imprinted genes of paternal origin promote greater wakefulness whereas imprinted genes of maternal origin favor more consolidated sleep. All these observations are consistent with a hypothesis that waking at night to suckle is an adaptation of infants to extend their mothers’ lactational amenorrhea, thus delaying the birth of a younger sib and enhancing infant survival.

This past December, science writer David Dobbs published an essay (2013) in the online magazine Aeon (aeon.co/magazine/) that purports to explain why the ‘selfish gene’ concept is outmoded and should be retired.  It elicited a good deal of commentary, and in early March, Aeon published responses (Sapolsky et al., 2014) to the original article from four individuals (two scientists, a genetic counselor, and a philosopher) as well as additional comments by Dobbs.  For those who are interested in this controversy, responses to the original Dobbs article were also posted elsewhere by Richard Dawkins (2013) and Jerry Coyne (2013a, b).  Below, I provide a sense of the arguments of Dobbs, the tenor of the criticisms of Dobbs’s piece, and selected other critiques of the gene-centric approach to evolution. Continue Reading »

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Crespi, B., Foster, K., & Úbeda, F. (2014). First principles of Hamiltonian medicine.
Philosophical Transactions of the Royal Society B: Biological Sciences, 369(1642). doi: 10.1098/rstb.2013.0366

We introduce the field of Hamiltonian medicine, which centres on the roles of genetic relatedness in human health and disease. Hamiltonian medicine represents the application of basic social-evolution theory, for interactions involving kinship, to core issues in medicine such as pathogens, cancer, optimal growth and mental illness. It encompasses three domains, which involve conflict and cooperation between: (i) microbes or cancer cells, within humans, (ii) genes expressed in humans, (iii) human individuals. A set of six core principles, based on these domains and their interfaces, serves to conceptually organize the field, and contextualize illustrative examples. The primary usefulness of Hamiltonian medicine is that, like Darwinian medicine more generally, it provides novel insights into what data will be productive to collect, to address important clinical and public health problems. Our synthesis of this nascent field is intended predominantly for evolutionary and behavioural biologists who aspire to address questions directly relevant to human health and disease.  More at PTRSB website 

The Cleveland Museum of Natural History invites applications for a postdoctoral fellow in Human Health and Evolutionary Medicine within the Division of Collections and Research.

The Museum is embarking on its Centennial Transformation Project, which will result in new exhibit galleries and research space.  As part of this project, a new gallery on human health is being created.  The museum seeks a postdoctoral fellow to help develop content and programs in the new human health gallery. Other duties will include managing content and coordinating with the exhibit design firm and a team of scientific advisors. The successful candidate will have a strong interest in public outreach and education and research experience in one of the following areas: 1) evolutionary medicine, 2) environmental health, 3) human biology, 4) human genetics.  The principal responsibility of the postdoctoral fellow will be exhibit-related activities, but research time can be negotiated depending on the fellow’s research program.  The position is for one year, starting July 1, 2014, but may be renewable for a second year.Applicants for this position should hold a M.D. or Ph.D. in a field related to human health (such as biochemistry, biological anthropology, cellular biology, genetics, immunology or physiology). The applicant should have a broad base of knowledge of human health, and demonstrated success in communicating science to the public is preferred.

The Cleveland region offers many opportunities for collaboration with other leading research programs at nearby institutions including Case Western Reserve University, University Hospitals, the Cleveland Clinic, Cleveland State University, and MetroHealth Hospitals, as well as a vibrant biotech community.   The museum itself also offers unique resources such as the Hamann-Todd Osteological Collection, a DNA laboratory, and the GreenCityBlueLake Institute.

TO APPLY

Please send a cover letter, curriculum vitae, the names and contact information for three professional references in single PDF file to:
Human Resources
Cleveland Museum of Natural History
1 Wade Oval Drive, University Circle
Cleveland, Ohio 44106
Hr@cmnh.org

 The list of people with an interest in evolution and medicine has been updated by Deryc Painter,  a graduate student in the Center for Biology and Society at ASU.  There are now 446 people on the list.

He began with the list from this site of self-identified medical professionals and research academics taking an evolutionary perspective to human health.  He added contributing authors and those cited in references from three recent textbooks of evolutionary medicine.  (Trevathan 1999, Stearns 1999, Perlman 2013)  He also added authors of articles in the 2010 special issue of Proceedings of the National Academy of Sciences on evolutionary medicine, and authors cited in Steve Stearns’ paper “Evolutionary Medicine: its scope, interest, and potential.  The resulting list provides a resource that should be very useful for connecting people in the field.  Please add your own information if it is not there already, and encourage other interested researchers, clinicians, and teachers to do the same.

  • Trevathan, W. R., Smith, E. O. & McKenna, J. J. 1999 Evolutionary medicine and health. New York, NY: Oxford University Press.
  • Stearns, S. C. 1999 Evolution in Health and Disease. New York, NY: Oxford University Press
  • Perlman, R. L. 2013 Evolution and Medicine. New York, NY: Oxford University Press.
  • Stearns, S. C. 2013.  Evolutionary Medicine: its scope, interest, and potential.  Proceedings of the Royal Society B. online  doi:10.1098/rspb.2012.1326

The 46 articles that were nominated  for the 2013 Omenn Prize are listed below.  The $5000 prize, sponsored by The Foundation for Evolution, Medicine, & Public Health, is made possible by a donation from Gilbert Omenn. Nominations closed on February 28, but the prize may be offered again next year.  The winner will be announced in April on the Foundation’s webpage and here at The Evolution, and Medicine Review.

To download the whole list click here     Omenn Prize articles EMR

To view the list, see below.

Continue Reading »

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