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Updated: Jul 5, 2026
07:34
FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
An unusual haplotype structure on human chromosome 8p23 derived from the inversion polymorphism
Libin Deng1, Yuezheng Zhang, Jian Kang
1Beijing Institute of Genomics, Chinese Academy of Sciences, P.R. China.
Human Mutation
|May 14, 2008
Summary
This study refines the genetic structure of a 3.8-Mb chromosomal inversion at 8p23, revealing population-specific genetic structures and selection signals. Haplotype analysis and principal component analysis (PCA) successfully identified inversion orientations and ancestral states.
Area of Science:
- Genomics
- Population Genetics
- Evolutionary Biology
Background:
- Chromosomal inversions are significant genomic variations influencing evolution and disease.
- Understanding the precise genetic structure of these variations is crucial for genetic studies.
Purpose of the Study:
- To refine the genetic structure of a 3.8-Mb inversion polymorphism at chromosome 8p23.
- To investigate population-specific genetic substructures and selection patterns associated with this inversion.
- To assess the utility of haplotype-based clustering methods for genome-wide inversion detection.
Main Methods:
- Utilized HapMap data including 1,073 single nucleotide polymorphisms (SNPs) from diverse populations (CEU, YRI, ASN).
- Employed principal component analysis (PCA) and neighbor-joining tree reconstruction to deduce haplotype orientations and identify clades.
- Validated inversion orientations using metaphase fluorescence in situ hybridization (FISH).
- Conducted population differentiation tests and relative extended haplotype homozygosity (REHH) analysis to detect selection signals.
Main Results:
- Successfully deduced inversion orientations for 418 haplotypes, identifying four distinct haplotype clades.
- PCA and phylogenetic analysis revealed population-specific genetic substructures.
- FISH analysis confirmed predicted inversion orientations.
- Identified the Human NCBI Build 36-inverted order as the likely ancestral orientation.
- Detected population-specific selection signals, including positive selection at XKR6 in the Asian (ASN) population.
Conclusions:
- Chromosomal inversion polymorphisms correlate with population-specific genetic structures and evolutionary selection patterns.
- Haplotype-based clustering methods like PCA are effective for scanning cryptic inversion polymorphisms genome-wide.
- This research provides insights into the maintenance of large chromosomal rearrangements during evolution.
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