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Updated: Jul 11, 2026

Personalized Peptide Arrays for Detection of HLA Alloantibodies in Organ Transplantation

Personalized Peptide Arrays for Detection of HLA Alloantibodies in Organ Transplantation

Published on: September 6, 2017

Locus and population specific evolution in HLA class II genes.

A M Valdes¹, S K McWeeney, D Meyer

¹Department of Integrative Biology, University of California at Berkeley 94720-3140, USA.

Annals of Human Genetics

|March 30, 2000

Summary

Human Leukocyte Antigen (HLA) class II loci show significant population and locus-specific variation in allele and amino acid frequencies. DRB1 exhibits the highest polymorphism, while Amerindian populations display lower diversity, suggesting potential roles for non-antigen recognition sites in antigen presentation.

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Immunopeptidomics: Isolation of Mouse and Human MHC Class I- and II-Associated Peptides for Mass Spectrometry Analysis

Immunopeptidomics: Isolation of Mouse and Human MHC Class I- and II-Associated Peptides for Mass Spectrometry Analysis

Published on: October 15, 2021

Area of Science:

Population genetics
Immunogenetics
Molecular anthropology

Background:

The human leukocyte antigen (HLA) class II molecules play a critical role in adaptive immunity by presenting antigens to T helper cells.
Understanding the population genetics of HLA class II loci is crucial for fields ranging from transplantation to disease association studies.

Purpose of the Study:

To investigate the population genetics of four HLA class II loci (DRB1, DQA1, DQB1, DPB1) across 22 diverse populations.
To analyze variation at both the allele and amino acid levels, focusing on antigen recognition sites (ARS) and other polymorphic sites.

Main Methods:

Utilized data from the Twelfth International Histocompatibility Workshop (1996).
Calculated heterozygosity and effective number of alleles to quantify genetic variation.
Applied homozygosity tests for neutrality and computed genetic distances between populations.

Main Results:

Observed substantial variation in polymorphism among populations and loci; DRB1 consistently showed the highest heterozygosity and effective number of alleles.
Confirmed lower allelic diversity in Amerindian populations compared to others.
Identified high variation at DRB1 ARS, and notably, at non-ARS sites in other loci, suggesting a potential role in antigen presentation.
DPB1 showed evidence of balancing selection, while DQB1 and DQA1 departed significantly from neutrality in numerous populations.

Conclusions:

HLA class II loci exhibit complex population-specific evolutionary patterns.
The high variation at non-ARS sites in some loci warrants further investigation into their function in immune response.
Balancing selection appears to be a significant evolutionary force shaping HLA class II diversity, though its influence varies across loci and populations.