Fig. 4. Differences in germline Ig V alleles affect the immune response.

A Ig V genes exist in many allelic forms, which differ in one or more nucleotides. Non-synonymous polymorphisms that change the amino-acid sequence may also alter the antigen-binding capacity of the resulting antibody. B For some V genes, the expression levels of alleles in heterozygous individuals are uneven, with one allele more frequently used in the repertoire than the other allele [37, 38, 106]. C There exist differences in the distribution of alleles among different population groups. As a result, vaccines relying on a specific Ig allele may not elicit equally efficient responses across ethnicities [23, 71].