title: FcgammaRIIA polymorphisms in Streptococcus pneumoniae infection.
abstract: Invasive pneumococcal disease continues to be a major cause of morbidity and mortality among children and adults worldwide. Effective host defence against Streptococcus pneumoniae depends on immunoglobulin G-mediated phagocytosis of the bacteria and it has been shown in vitro that the FcgammaRIIA polymorphism (FcgammaRIIA-R131 vs FcgammaRIIA-H131) determines the capacity of immunoglobulin G2-mediated phagocytosis via this receptor. In this study, we evaluated FcgammaRIIA polymorphisms in children with pneumococcal sepsis and a number of control groups in order to investigate a possible association of FcgammaRIIA genotypes with Streptococcus pneumoniae infection. The distribution of the genotypes differed in these populations. The frequency of homozygosity for FcgammaRIIA-R/R131 in the patients was significantly higher than that in the healthy random donor population (43%vs 21%, P < 0.05). The frequencies of FcgammaRIIA-H/H131 were similar among all groups of individuals, while the incidence of the heterozygous FcgammaRIIA-R/H131 was lower (35%vs 52%, P < 0.05). Thus, it appears that the FcgammaRIIA-H131 polymorphic form, even in the heterozygous form, may be protective for pneumococcal sepsis and children with FcgammaRIIA-R/R131 genotype could be more at risk of infection with invasive Streptococcus pneu-moniae.
authors.affiliation: Australian Red Cross Blood Service-Endeavour, Sydney, New South Wales, Australia. fyuan@arcbs.redcross.org.au
authors.forename: Fang Fang
authors.initials: FF
authors.lastname: Yuan
authors.forename: Melanie
authors.initials: M
authors.lastname: Wong
authors.forename: Natalia
authors.initials: N
authors.lastname: Pererva
authors.forename: Joanna
authors.initials: J
authors.lastname: Keating
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Davis
authors.forename: Jenny A
authors.initials: JA
authors.lastname: Bryant
authors.forename: John S
authors.initials: JS
authors.lastname: Sullivan
mesh_terms: D015703:Antigens, CD / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D011008:Pneumococcal Infections / Q000235:genetics / Q000276:immunology*; D011110:Polymorphism, Genetic; D017452:Receptors, IgG / Q000235:genetics*; D012307:Risk Factors; D013296:Streptococcus pneumoniae / Q000276:immunology*
chemical_list: D015703:Antigens, CD; C080568:Fc gamma receptor IIA; D017452:Receptors, IgG