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qKAT: Quantitative Semi-automated Typing of Killer-cell Immunoglobulin-like Receptor Genes
Published on: March 6, 2019
The extensive polymorphism of KIR genes
Derek Middleton1, Faviel Gonzelez
1Transplant Immunology Laboratory, Royal Liverpool and Broadgreen University Hospital and School of Infection and Host Defence, Liverpool University, Liverpool, UK. Derek.Middleton@rlbuht.nhs.uk
Immunology
|December 24, 2009
Summary
Human natural killer (NK) cell functions are regulated by killer cell immunoglobulin-like receptors (KIR). KIR gene complex polymorphism significantly impacts NK cell activity and varies across global populations.
Area of Science:
- Immunology
- Genetics
Background:
- Natural killer (NK) cell functions are governed by diverse antigen receptors, notably killer cell immunoglobulin-like receptors (KIR).
- The KIR gene complex is highly polymorphic, comparable to the human leucocyte antigen (HLA) complex, and located in a variable region of the human genome.
Purpose of the Study:
- To review the extensive polymorphism within the KIR gene complex.
- To highlight the variability in KIR gene and allele frequencies across different global populations.
- To introduce a new website for accessing KIR frequency data.
Main Methods:
- Review of existing literature on KIR gene polymorphism.
- Analysis of KIR gene, allele, and genotype frequencies in various populations.
- Classification of KIR genes into inhibitory (A) and activating (B) haplotypes.
Main Results:
- The KIR gene complex exhibits significant polymorphism, including the presence or absence of genes and diverse alleles.
- KIR gene and allele frequencies differ substantially among worldwide populations, leading to unique individual KIR repertoires.
- KIR haplotypes (A and B) influence NK cell function, with variations in gene copy number and functional differences at the allele level.
Conclusions:
- The high degree of KIR polymorphism, encompassing gene presence/absence, allele frequencies, and haplotype variations, is crucial for understanding NK cell diversity.
- Functional differences in KIR alleles, including protein expression and HLA ligand avidity, further contribute to the complexity of NK cell regulation.
- The presented website serves as a valuable resource for researchers studying KIR genetics and its population-level variations.
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