IgA deficiency

Selective IgA deficiency is the most common primary immunodeficiencies. B-lymphocytes are present there but are unable to change into the IgA-producing plasma cells. Because all the other antibodies are normal or near-normal, the condition is called selective IgA deficiency. Haplotype analysis, linkage disequilibrium, and homozygosity mapping indicated that HLA-DQ/DR is the major IGAD1 locus, and suggest the autoimmune pathogenesis of IgAD/CVID. It has been associated with other chromosomal abnormalities involving chromosome 18.

Alternative names


Selective IgA deficiency

Selective deficiency of immunoglobulin A

Selective deficiency of Gamma-A-globulin


  • Deficiencies predominantly affecting antibody production
    • Selective deficiency of IgG subclass, IgE and/or IgA class or subclass




%137100 Immunoglobulin a deficiency susceptibility 1; IGAD1

Cross references


Incidence varies between countries and racial group. Between 1: 400-800 individuals will be affected.