valley flower sunset

Characterizing the Importance of Environmental Exposures, Interactions between the Environment and Genetic Architecture, and Genetic Interactions:

New Methods for Understanding the Etiology of Complex Traits and Disease


Much of the field of genetic epidemiology has focused nearly exclusively on the relationship between genetic variation and disease outcome. However, identifying important environmental factors, and their interaction with genetic variation, is key for explaining complex traits and predicting the risk of developing disease. Further, much of the exploration of the relationship between genetic variation and outcome has ignored genetic interactions and the possibility for epistasis. The lack of heritability explained, and lack of models predictive of disease outcome, have led to more discussion of the importance of identifying contributors to disease beyond pursuit of single genetic variant – single outcome analyses.

There are multiple research opportunities for identifying important environmental contributions to disease, from individual environmental exposures to the “exposome”: the totality of exposures of each individual over the life course. For some diseases there are known environmental exposures that contribute risk, such as smoking or UV exposure and cataracts. There are other disorders where identification of environmental contribution to risk and disease severity are very active areas of exploration and discovery, such as understanding the etiology of autism. Identifying important exposures contributing to outcome from large numbers of possible exposures and toxins is a challenge, and high throughput screens are an important approach as well as methods such as environment-wide association studies (EWAS).

It is also important to understand the relationship between genetic architecture and outcome by exploring interactions between genetic loci. Epistasis has been detected in model organisms such as drosophila, and there is evidence of epistasis contributing to diseases like Alzheimer’s, diabetes, and cancer . There is also evidence of epistasis between rare variants affecting complex diseases. Detecting epistasis in humans has been challenging due to issues including computational limitations, especially for interactions higher than pairwise; decreased power to detect interactions when compared to main effects; and difficulties with replicating significant epistatic models across heterogeneous samples. There are many opportunities for advancing methods for detecting gene-gene interactions.

Session Topics

The goal of this session is to encourage research and tool development for greater understanding of the impact of environmental exposures on complex traits and disease outcomes, elucidating the relationship between genetic variation and environmental exposure, and the exploration of genetic interactions and outcomes. Thus we will be seeking papers including, but not limited to, the following topics:

  • High-throughput identification of important environmental exposures, including methods for high-throughput toxicological screening
  • New methods for identification of important environmental exposures for diseases such as autism as well as complex traits such as obesity
  • Analyses exploring the interaction between environmental exposures and genetic architecture, from SNPs to copy-number variants
  • Analyses exploring the interaction of environmental exposures and long non-coding RNA expression
  • Systems-biology approaches, including the use of networks, for seeking trends across complex data that incorporate multiple –omic measurements and environmental data
  • Statistical models and other tools to better understand genetic interactions
  • Exploring phenomena affecting the interplay between genes and complex disease
  • Integrating interaction and pathway association analysis
  • Use of interaction studies and functional information in translating GWAS statistics into biology
  • Methods for considering genetic heterogeneity in interactions
  • What it means to replicate an epistatic interaction: at the level of a SNP, region, gene, or pathway

Other topics within the subject area are welcome.

Session Co-Chairs

  • Sarah A. Pendergrass, M.S. Ph.D.
    Center for System Genomics
    The Pennsylvania State University

  • Shefali Setia Verma, M.S.
    Center for System Genomics
    The Pennsylvania State University

  • Molly Hall, M.S.
    Graduate Student
    Center for System Genomics
    The Pennsylvania State University

  • Jason H. Moore, M.A. M.S. Ph.D.
    The Geisel School of Medicine
    Dartmouth College

  • Brendan Keating, Ph.D.
    Children's Hospital of Pennsylvania

  • Scott Selleck, M.D. Ph.D.
    The Pennsylvania State University

  • Greg Gibson, Ph.D.
    Georgia Tech University

  • Folkert Asselbergs, M.D. Ph.D.
    University Medical Center Utrecht

  • Heather Volk, Ph.D.
    University of Southern California

  • Issac Pessah, Ph.D.
    UC Davis Children's Center for Environmental Health

  • Dennis Wall, Ph.D.
    Stanford University

  • Daniel B. Campbell, Ph.D.
    University of Southern California

Submission Information

Please note that the submitted papers are reviewed and accepted on a competitive basis.

Important Dates

  • Paper submissions due: July 31, 2014 Extended deadline: August 6, 2014
  • Notification of paper acceptance: September 9, 2014
  • Camera-ready final paper deadline: October 1, 2014
  • Abstract deadline for unreviewed posters: November 17, 2014

Paper Format

Please see the PSB paper format template and instructions at

The file formats we accept are: postscript (*.ps) and Adobe Acrobat (*.pdf)). Attached files should be named with the last name of the first author (e.g. or altman.pdf). Hardcopy submissions or unprocessed TeX or LaTeX files will be rejected without review.

Each paper must be accompanied by a cover letter. The cover letter must state the following:

  • The email address of the corresponding author.
  • The specific PSB session that should review the paper or abstract.
  • The submitted paper contains original, unpublished results, and is not currently under consideration elsewhere.
  • All co-authors concur with the contents of the paper.

Submitted papers are limited to twelve (12) pages in our publication format. Please format your paper according to instructions found at If figures cannot be easily resized and placed precisely in the text, then it should be clear that with appropriate modifications, the total manuscript length would be within the page limit.