Otherindependent cross-checkabstract checked I-SYS-104 standard review
Genes explain a minority of chronic disease
Genetic Factors Are Not the Major Causes of Chronic Diseases.
Overview
Rappaport SM. PLoS One 2016 · PMID 27105432 · DOI 10.1371/journal.pone.0154387
Genetic factors explained a median of 18.5% of the risk of 28 chronic diseases.
Does the study support the specific claim? Partly · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Estimate genetic share.
- How was the study done?
Twin data analysis.
- How many people, animals or samples were studied?
28 diseases.
- What was actually found?
Genes minor.
- How large was the observed effect?
Median 18.5%.
- What do the results mean in everyday life?
Disease is largely not fate.
- What are the study's limitations?
Assumptions.
- What does it say about Elawady's specific claim?
Partly supports the claim's 'not fate' part.
- Do the results apply to Germany and Europe?
High.
- What can explicitly not be concluded from this study?
Which exposures matter.
Scientific in-depth review
1. Full reference
- Authors
- Rappaport SM
- Journal
- PLoS One
- Year
- 2016
- Identifier
- PMID 27105432 DOI 10.1371/journal.pone.0154387
- Verification
- verified – PubMed efetch 2026-10-26 + Crossref
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
No competing interests (PubMed)
2. Research question
What fraction of chronic disease risk is attributable to genetics (plus shared exposures)?
3. Study design and population
- Study design
- Other – Twin-data based estimation of genetic population attributable fractions
- Population
Western European monozygotic twins; mortality statistics
- Country
Western Europe
- Period
Published 2016
- Sample size
28 chronic diseases
- Inclusion and exclusion criteria
Published MZ twin data
4. Methods and endpoints
- Exposure / intervention
Genetics plus shared exposures
- Comparator
not applicable
- Endpoints
Genetic PAF
- Statistical methods
PAF estimation
5. Actual results
- Results
Genetic PAFs ranged 3.4% (leukaemia) to 48.6% (asthma), median 18.5%; cancers median 8.26%. 16.4% of 1.53 million Western European deaths in 2000 attributable to genetics plus shared exposures.
- Absolute risks
16.4% of deaths
- Authors' conclusion
Genetic factors are not the major causes of chronic diseases; exposome research is needed.
6. Strengths
- Simple, transparent approach
7. Weaknesses
- Assumptions about twin data
- Non-genetic share includes chance and all environmental factors
8. Risk of bias
- Orienting tool
- none applicable
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Modelling assumptions.
9. Assessment of the statistical interpretation
Non-genetic share is not attributable to any specific exposure.
10. Relevance to the specific claim
Supports the 'disease is not genetic fate' part of C-SYS-03; does not show that food, medicines or cosmetics are the main non-genetic causes.
11. Independent contrary findings
12. Transferability to Germany and Europe
High.
13. Overall methodological judgement
Partial support for the 'not fate' kernel.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | not applicable |
| Directness | indirect |
| Reproducibility | unknown |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
15. Linked fact checks
- Chronic disease is mostly a cumulative reaction to what enters the body daily - contaminated food, medicines and cosmetics - not a fate that comes from outside. – Studies with mixed or unclear results