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A POPULATION BASED STUDY OF THE GUT MICROBIOME: A Pilot Project with the Wisconsin Longitudinal Study
A POPULATION BASED STUDY
OF THE GUT MICROBIOME:
A Pilot Project with the Wisconsin Longitudinal
Study
Research Team:
• Pamela Herd, Public Affairs and Sociology
• Federico Ray, Bacteriology
• Kerryann DiLoreto, UW Survey Center
• Karen Jacques, UW Survey Center
With Support from:The National Institute on Aging
The National Science Foundation
The Social Security Administration
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What is the Gut Microbiome?
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Microbes are Everywhere
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3,500,000,000,000,000,000,000,000,000,000 microbes in oceans
260,000,000,000,000,000,000,000,000,000 microbes in the soil
1,000,000,000,000,000,000,000 stars in the universe
100,000,000,000,000 microbes in your gut
7,100,000,000 humans on Earth
From: Whitman, et al. (1998) PNAS 95:6578
What are Microbes?In general, any organism at the microscopic
scale (requires a microscope to view)
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The Microbiome
• Sequencing, which started in the 2000s, enables
us to study the 99% of microbes we can not
culture.
• The complete collection of genomes from a
community of microbes is called a MICROBIOME.
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• ~ 150 species per individual (large inter-personal variation)
• An enormous genetic repository
• 1x1011 organisms per milliliter
The Gut Microbiota: A Metabolic Organ
• Critical for processing food, for example.
Why Would Social Scientists Study It?
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There is a Strong Relationship between the Gut Microbiota and Human Health
• Inflammatory bowel disease [Sartor. Gastro 2008]
• Irritable bowel syndrome [Malinen. Am J Gastro 2005]
• Pouchitis [Komanduri. Clin Gastro Hepatol. 2007]
• Necrotizing enterocolitis [Wang Y. ISME J. 2009]
• Coeliac disease [De Palma G. BMC Microbiology 2011]
• Arthritis [O'Dell. Arthritis Rheum. 2006]
• Atherosclerosis [Stepankova. J Atheroscler Thromb 2010]
• Diarrhea (C. diff) [Change. J. Infect. Dis 2008]
• Metabolic syndrome [Vijay-Kumar. Science 2010]
• Diabetes [Wen. Nature 2008]
• Obesity [Ley. Nature 2006]
• Autism [Williams. Mbio 2012]
• Colorectal cancer [Scanlan. Environ Micro. 2008]
It’s Shaped by the Environment
• Distinct from our human genome in origin and plasticity
• Importance of early Life: Origin--we are all born germfree
• Plasticity: microbial community composition varies between
individuals and within individuals over time
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We Can Help Address Existing Data and Substantive Limitations
• Small samples sizes—if they have extensive phenotypic
data.
• Select samples
• Limited phenotypic data
• Expertise in survey data collection.
• Expertise in the influence of the social environment on
health.
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How Can We Study It?
A Pilot Study with the Wisconsin
Longitudinal Study
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The Process
• Focus group Interviews in Summer of 2014
• Field collection in the October 2014-February 2015
• 427 Samples (76% Response Rate with no refusal
conversion)
• Sibling Pairs
• Spousal Pairs
• 100% response rate for the SAQ.
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Stool Sample Container:
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Shipping Box
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Place the chilled ice pack directly on top of the
sample. Replace the Nano Cool cartridge on top
and close the box.
Why Were We Successful?
• The science is intuitive.
• Older adults frequently engage in this type of activity.
• In-person drop-off and pick-up.
• Limited information provided in advance letter.
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What Might We Learn?
The Largest Existing Microbiota Study
with such Extensive Phenotypic Data
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Correlational Studies
• What is the relationship between environmental exposures
(e.g., drinking water) and our gut microbiome?
• What is the relationship between the gut microbiome
behavioral and social outcomes?
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Embedding Animal Model Experiments
• The case of obesity.
• The case of cognition.
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Conclusion
• Social scientists can make significant contributions.
• These have to be true partnerships. I won’t be running my
own mice experiments!
• It’s feasible. If anything, we have demonstrated the
feasibility of collecting these samples in a population based
design.
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GradGrad
SpouseSibling
Sib
Spouse Total
Education
HSGrad 71 50 61 46 63
associatedegree 2 25 5 19 7
bachelor'sdegree 19 10 22 31 20
master'sdegreeorhi 8 15 12 4 10
BMI
Underweight 0.6 0.0 0.7 0.0 0.5
Normal 27.9 34.9 35.5 36.4 32.2
Overweight 39.7 38.1 29.7 21.2 34.6
Obese 31.8 27.0 34.1 42.4 32.7
PercentFemale 49.2 51.9 51.4 69.2 51.6
MeanAgein2015 76.13 75.53 73.93 72.62 75.05
MeanIQ 104.18 99.30 105.82 106.45 104.32
How do we study microbes?
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Sample
Agar Plate
Induce Growth
Pure Culture
Insights into microbial
function are primarily
from pure cultures
Major Challenge: We
can only culture ~1% of
all microbes on Earth!
The DNA Sequencing Revolution
• In the 2000s, Researchers began applying DNA
sequencing to Microbial Genomes.
• Today, microbial genome sequencing is routine
and easily performed in a laboratory
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Microbes Power (almost) Everything
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Global Environment:
Carbon, Nitrogen, Sulfur & Phosphorous cycles
Disease and Health:
Pathogens & Beneficial Microbes
Antibiotic Production
Food:
Fermented Beverages: Beer & Wine
Cheese, Yogurt, and other Dairy products
Fermented Foods: Sauerkraut & Chocolate
Food additives: Pre/Pro-biotics, Amino Acids, Vitamins
Agriculture:
Biofertilizers, plant growth enhancers, and disease resistance
