HLA DQA-DQB haplotypes in a Swedish population

Area of Science:

• Immunogenetics
• Molecular Anthropology

Background:

• The Human Leukocyte Antigen (HLA) complex plays a crucial role in immune responses.
• Understanding HLA allele and haplotype frequencies is vital for population genetics and transplantation studies.

Purpose of the Study:

• To determine the frequencies of HLA-DQA1 and HLA-DQB1 alleles and their haplotype combinations in a Swedish blood donor population.
• To compare haplotype frequencies derived from deduced allele combinations with those calculated from phenotypic data.

Main Methods:

• Analysis of 94 Swedish blood donor samples using the Polymerase Chain Reaction Sequence Specific Oligonucleotide (PCR-SSO) typing technique.
• Identification of HLA-DQA1 and HLA-DQB1 alleles and deduction of 17 common haplotype combinations.
• Comparison of haplotype frequencies calculated by two different methods: deduced from allele combinations and from phenotypic data.

Main Results:

• Seven HLA-DQA1 and 12 HLA-DQB1 alleles were identified.
• A total of 17 haplotype combinations were deduced.
• No significant differences were observed in haplotype frequencies between the deduced and phenotypic calculation methods.
• The most frequent haplotypes identified were DQA1*0301-DQB1*0302, DQA1*0501-DQB1*0201, DQA1*0101-DQB1*0501, and DQA1*0102-DQB1*0602, each with frequencies exceeding 0.130.

Conclusions:

• The PCR-SSO method effectively identified HLA-DQA1 and HLA-DQB1 alleles and their haplotypes in the studied population.
• Haplotype frequency calculations are robust regardless of whether deduced allele combinations or phenotypic data are used.
• The identified frequent haplotypes provide valuable data for immunogenetic and population studies in Sweden.