Association of HLA-*08:DRB1*03 with immunoglobulin A-deficiency

Susceptibility to IgA deficiency (IgAD) is strongly associated with alleles of HLA, but it is not equally strong in different human populations. Therefore, the goal of this study was to determine the HLA-A, -B and -DRB1 antigenic and haplotypic frequencies in unrelated Polish Caucasian IgA-deficient patients who had never been examined so far in this respect.

The HLA alleles were determined by means of low resolution polymerase chain reaction with sequence specific primers (PCR-SSP) method in a group of IgA-deficient patients and control subjects from the same area.

The HLA-DRB1*03 allele showed the strongest association with IgA deficiency in the Polish population (OR=6.6, p cor=0.0084). The HLA-B*08 allele was also associated with predisposition to the disease (OR=6.22, p cor=0.033). These significant associations could be explained in the context of a positive association of IgAD with the HLA-B*08:DRB1*03 haplotype, previously reported in other Caucasoid populations from Northern and Central Europe. In our group the HLA-B*08:DRB1*03 haplotype was present in 52.9% of IgA-deficient patients comparing to 9.9% in controls (p< 0.00011). A positive association of HLA-B*08 and DRB1*03 was stronger in IgA-deficient males than in females from the same group.

Immunoglobulin A deficiency in Polish population is strongly associated with HLA-B*08:DRB1*03 haplotype rather than with single alleles.