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Inter-individual genomic heterogeneity within European population isolates
Paolo Anagnostou1,2, Valentina Dominici1, Cinzia Battaggia1
1Dipartimento di Biologia Ambientale, Università di Roma "La Sapienza", Rome, Italy.
Plos One
|October 10, 2019
Summary
Genetic analysis of 28 European populations reveals that isolated groups are not always genetically uniform. Some isolates show high inter-individual genomic heterogeneity, challenging long-held assumptions in population genetics.
Area of Science:
- Human Population Genetics
- Genomics
- Evolutionary Biology
Background:
- Studies since the 1970s have explored isolation's effects on genetic variation within and among human populations.
- Limited research exists on genomic heterogeneity within isolated populations, despite potential disruption from recent admixture or subdivision.
Purpose of the Study:
- To analyze genomic heterogeneity within isolated European populations.
- To challenge the paradigm of population isolates as genetically uniform entities.
- To propose methods for monitoring inter-individual heterogeneity in disease-gene association studies.
Main Methods:
- Literature data analysis of 87,815 autosomal single-nucleotide polymorphisms.
- Inclusion of data from 28 diverse European populations.
- Focus on the distribution of variance in intra-population diversity measures across individuals.
Main Results:
- Inter-individual genomic heterogeneity in isolated populations is comparable to, or even exceeds, that of open populations.
- Three highly inbred Italian isolates (Sappada, Sauris, Timau) exhibited significantly higher heterogeneity, likely due to recent genetic introgression.
- Results challenge the traditional view of population isolates as genetically uniform.
Conclusions:
- Population isolates are not necessarily genetically homogeneous.
- Recent genetic events like introgression can significantly increase inter-individual heterogeneity.
- Understanding genomic heterogeneity is crucial for accurate disease-gene association studies in isolated populations.
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