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Learn More About Pegs


The goal of the Personalized Environment and Genes Study (PEGS), formerly the Environmental Polymorphisms Registry or EPR, is to discover how our environment and genes affect our health, which will improve the prevention and treatment of human diseases. The PEGS data is a comprehensive and diverse database of health, exposure, medical and genetic data that will enable scientists to improve our understanding of disease mechanisms and identify novel risk factors for various diseases. These discoveries will help improve the prevention and treatment of various diseases and help develop disease prevention approaches that could benefit all populations.


Individuals living in the state of North Carolina, United States and 18 years or older are eligible to enroll in the Personalized Environment and Genes Study . As of 2020, there are almost 20,000 participants enrolled in the PEGS study. The PEGS cohort represents a diverse population in terms of age, gender, race and ethnicity thus representing people from all walks of life.


PEGS is a unique study that combines many different types of data, including surveys, biological samples, electronic health records, genotyping data, whole genome sequencing data and geographic information systems (GIS) data.

The PEGS study consists of the following data:

  • Survey data
    • Health & Exposure Survey – questions on general health, family’s health history, occupational exposures and lifestyle
    • External Exposome Survey – questions on residential and occupational environmental exposures
    • Internal Exposome Survey – medication use, physical activity, stress, sleep, and diet
    • Eczema Screener – additional questions about eczema diagnosis from selected participants
    • Diabetes Screener – additional questions about diabetes diagnosis from selected participants
    • Demographic Information – basic information such as age, weight, race, places lived, etc.
    • Core Medical History Survey – medical history data such as current or past diseases, medical conditions, smoking history, alcohol history, sleep, surgical history, medications, etc.
  • Blood samples
  • Urine samples
  • Electronic health records
  • Genotyping and whole genome sequencing data

The PEGS study administers multiple surveys to collect demographic, health, lifestyle, medications use, diet, family history of diseases and environmental exposure data from the enrolled participants. Survey questions cover a wide range of diseases – cardiovascular, endocrine, respiratory, neurologic, digestive, etc., and exposures – residential, occupational, chemical, metal, ultraviolet (UV), etc. Participants also provide a blood sample which is used for lab and genetic tests such as DNA genotyping and/or sequencing. Participants will also be asked to provide a urine sample which will be used for several different tests including certain environmental toxins. Participant demographic information is used to obtain environmental exposure data, such as air pollution levels, exposure levels to industrial, agricultural, or animal husbandry chemicals from publicly available geographic information systems databases. Participants, whose medical records are stored with the Duke or University of North Carolina (UNC) healthcare systems, will be asked if they consent to share portions of their electronic health records. Over time, participants may be asked for additional data or biospecimens or to join follow-up studies further enriching the PEGS cohort data. Participants have the option to provide or decline consent to any of these requests. All data and biological samples provided by the participants to the PEGS study are stored in a secure location at NIEHS. All participant data is de-identified before publication.

Scientific Research

An individual’s risk for a disease and his or her response to treatment is influenced by many factors including his or her genetic makeup, environment, diet, lifestyle, other health conditions, etc. For example, skin cancer risk is influenced by skin color, family history of skin cancer, exposure to sunlight or UV light, sunscreen use, history of sunburn, etc. Additionally, the interactions between these various factors can also influence disease risk. Various scientific studies have shown that genes modify how environmental exposures affect our health. For the skin cancer example, where skin color is determined by our genes, prolonged exposure to sunlight or UV light puts individuals with lighter skin color at a much higher risk of skin cancer compared to individuals with darker skin color. Hence, it is important to jointly study the effects of these factors and their interactions to assess disease risk.

Scientists are using various statistical and analytical methods on the comprehensive data provided by the PEGS participants to investigate how environment, diet, lifestyle and genetic factors collectively affect human health. Unlike other studies that focus on a single disease or environmental exposure, the PEGS data contains information on a large number of diseases and environmental exposures, along with diet, lifestyle and genetic data. This richness and diversity of the PEGS data allows scientists to conduct a multitude of studies, including but not limited to:

  • Identifying novel genetic and environmental factors that increase risk of several common diseases such as diabetes, heart disease, stroke, multiple sclerosis, psoriasis, rheumatoid arthritis, allergies, asthma, cancer and many others
  • Identifying how multiple genetic and environmental factors jointly increase disease risk
  • Identifying the interaction of genetic and environmental factors affecting disease risk
  • Developing risk scores using the comprehensive genetic data and varied environmental exposures that could be used in conjunction with clinical data to improve disease risk prediction
  • Identifying differences in risk factors for people of different ages, race or ethnicity
  • Investigating shared exposures and diseases to identify co-occurrences of diseases and environmental exposures that are associated with multiple diseases
  • Improving our understanding of the causes and mechanisms of various diseases

To know more about the scientific research being done using the PEGS data, please visit the NIEHS PEGS website.

Last Reviewed: June 16, 2024