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Updated: Aug 6, 2026
14:06
Detection of Rare Genomic Variants from Pooled Sequencing Using SPLINTER
Published on: June 23, 2012
Human genetic diversity: Lewontin's fallacy
1Gonville and Caius College, Cambridge, CB2 1TA, UK. awfe@cam.ac.uk
Summary
Genetic variation within human populations is significant, but differences between ethnic groups are also important. Population divisions are genetically justified, as key information lies in data correlations, not just individual variations.
Area of Science:
- Population Genetics
- Human Evolutionary Genetics
Background:
- Popular science often states 85% of human genetic variation is within populations, 15% between.
- This statistic has been used to argue against the genetic basis of human population or ethnic groups.
Purpose of the Study:
- To re-evaluate the genetic justification for human population divisions.
- To demonstrate that genetic variation between populations is significant and not solely based on individual differences.
Main Methods:
- Analysis of genetic variation data, focusing on correlation structures.
- Utilizing a simple genetical example to illustrate the logic.
Main Results:
- The commonly cited 85/15 split underestimates inter-population genetic differences.
- Crucial information distinguishing populations is embedded within the correlation structure of genetic data.
Conclusions:
- The conclusion that human population divisions are not genetically justified is unwarranted.
- Genetic data, when analyzed correctly (considering correlations), supports the significance of population-level genetic differences.
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