Identification of the HLA-DQB1*06:123 allele in an unrelated stem cell donor from the Saudi Registry

Area of Science:

• Immunogenetics
• Molecular biology

Background:

• Human Leukocyte Antigen (HLA) genes are highly polymorphic.
• Specific HLA alleles play critical roles in immune responses and disease susceptibility.

Purpose of the Study:

• To characterize the genetic differences between two specific HLA-DQB1 alleles.
• To identify the molecular basis for variations between HLA-DQB1*06:123 and HLA-DQB1*06:29.

Main Methods:

• Nucleotide sequencing of HLA-DQB1 alleles.
• Comparative sequence analysis to identify substitutions.
• Amino acid translation to determine protein sequence changes.

Main Results:

• HLA-DQB1*06:123 was found to differ from HLA-DQB1*06:29 by six nucleotide substitutions.
• These nucleotide changes resulted in five amino acid substitutions in the HLA-DQB1*06:123 allele compared to HLA-DQB1*06:29.

Conclusions:

• The genetic divergence between HLA-DQB1*06:123 and HLA-DQB1*06:29 is defined by specific nucleotide and amino acid alterations.
• Understanding these molecular differences is crucial for immunogenetic studies and HLA typing.