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09:34
Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease
Published on: April 4, 2018
A human derived SSADH coding variant is replacing the ancestral allele shared with primates.
Ofelia Leone1, Paola Blasi, Francesca Palmerio
1Department of Cell Biology, University of Calabria, Rende, Italy.
Annals of Human Biology
|March 27, 2007
Summary
Derived alleles in NAD(+)-dependent succinic semialdehyde dehydrogenase (SSADH) are increasing globally, replacing ancestral variants. This pattern suggests natural selection may be driving these genetic changes in human populations worldwide.
Area of Science:
- Human population genetics
- Molecular evolution
- Genomics
Background:
- Reports indicate ancestral alleles are frequent in Africa, while derived variants are common outside Africa.
- These frequency patterns suggest potential neutral or non-neutral evolutionary processes.
Purpose of the Study:
- Investigate worldwide frequencies of two non-synonymous variants in NAD(+)-dependent succinic semialdehyde dehydrogenase (SSADH).
- Search for signatures of natural selection favoring derived alleles in SSADH.
Main Methods:
- Compiled genetic data from 1574 individuals across 60 global populations.
- Correlated SSADH haplotype frequencies with 260 single nucleotide polymorphism (SNP) markers and known selected markers.
Main Results:
- The c.538C SSADH variant is replacing the ancestral c.538T variant globally.
- Found significant correlation between SSADH derived alleles and Microcephalin (MCPH1) frequencies worldwide.
- Observed concerted allele frequency changes, particularly in Asian populations.
Conclusions:
- Robust correlation analysis across diverse populations can identify co-evolving genomic regions.
- Suggests potential shared evolutionary pressures influencing allele frequency dynamics for specific genes.
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