KIR haplotypes defined by segregation analysis in 59 Centre d'Etude Polymorphisme Humain (CEPH) families

Area of Science:

• Immunogenetics
• Human Genetics
• Molecular Biology

Background:

• The killer cell immunoglobulin-like receptor (KIR) gene cluster displays significant allelic and haplotypic diversity.
• KIR locus variation is increasingly linked to various human diseases, similar to HLA loci.
• Advancements in sequencing entire KIR haplotypes have facilitated detailed diversity characterization.

Purpose of the Study:

• To investigate the extent of KIR haplotypic variability in individuals of northern European descent.
• To identify unique KIR haplotypes and their frequencies within this population.
• To establish a foundational dataset for interpreting KIR-related disease associations in European populations.

Main Methods:

• Genotyping of 59 CEPH families for the presence/absence of all KIR genes.
• Limited allelic subtyping at selected KIR loci.
• Linkage Disequilibrium (LD) analysis to infer haplotypic structure.

Main Results:

• Identification of 20 distinct KIR haplotypes, with the previously defined A haplotype being the most frequent (frequency = 0.52).
• Discovery of several uncommon haplotypes, likely resulting from unequal crossing over events.
• Significant negative and positive linkage disequilibrium observed between specific gene pairs, offering insights into haplotypic architecture.

Conclusions:

• The study characterizes KIR gene content variability in a northern European cohort.
• The identified haplotypes and LD patterns serve as a crucial resource for disease association studies in European populations.
• This genetic resource aids in understanding the role of KIR diversity in human health and disease.