Recurrent otitis media: genetic immunoglobulin markers in children and their parents

The likelihood that hereditary factors play a significant role in the development of recurrent acute otitis media (rAOM) in children has been suggested. The genetically determined immunoglobulin variants, Gm and Km, are useful tools for mapping out the genetic loci involved in antibody responses. Certain Gm and Km types, G2m(23) and Km(1), appear to be linked to genes which regulate the concentrations of antibodies to pneumococcal polysaccharide antigens in adults. Our aim was to identify such immunoglobulin markers in rAOM children, since these children have extremely low concentrations of IgG antibodies against the pneumococcal types associated with this disease. The markers G1m(1), G1m(2), G1m(3), G2m(23) and Km(1) were identified in 20 families, each comprising 1 parent and 1 child with a history of rAOM and 1 parent free from rAOM. In addition, G2m(23) was identified in 47 children without AOM. The distribution of Gm and Km markers between rAOM and healthy subjects did not differ significantly. If anything, rAOM children exhibited a high rate of the G2m(23) marker, whereas earlier observations in adults have demonstrated low responders to polysaccharide antigens to be preferentially G2m(-23). Our findings indicate that mechanisms responsible for the low concentrations of antibodies to pneumococcal polysaccharides in rAOM children may differ from those causing certain adults to be low responders when exposed to pneumococcal polysaccharides.