A gene feature enumeration approach for describing HLA allele polymorphism

Area of Science:

• Immunogenetics
• Molecular Biology
• Bioinformatics

Background:

• Next-generation sequencing (NGS) for Human Leukocyte Antigen (HLA) genotyping reveals numerous synonymous and non-coding sequence variants.
• Current HLA allele nomenclature inadequately describes the distribution of sequence polymorphism across gene features (untranslated regions, exons, introns).
• HLA allele naming is not feasible when antigen-recognition domain (ARD) encoding exons are absent.

Purpose of the Study:

• To propose a novel system for describing HLA polymorphism based on HLA gene features (GFs).
• To enable a more granular analysis and discussion of HLA sequence variants.
• To facilitate the analysis of GFs independently of ARD-encoding exon sequences.

Main Methods:

• Development of a system to enumerate unique nucleotide sequences for each GF within an HLA gene.
• Establishment of a GF enumeration notation to record these sequences.
• Application of the GF system to analyze and discuss HLA polymorphism.

Main Results:

• The proposed GF system provides a method for enumerating unique nucleotide sequences for each gene feature.
• This notation allows for a more detailed dissection of allele-level HLA polymorphism.
• The system enables discussion and analysis of GFs even when ARD-encoding exon sequences are not available.

Conclusions:

• The GF enumeration notation offers a more comprehensive approach to describing HLA polymorphism compared to traditional allele naming.
• This system enhances the analysis of sequence variants identified by NGS.
• The GF system supports the study of HLA genetic diversity and evolution, particularly in the context of non-coding and synonymous variations.