Article

Functional polymorphisms in the FCN2 gene are not associated with invasive pneumococcal disease.

The Wellcome Trust Centre for Human Genetics, University of Oxford, UK.
Molecular Immunology (impact factor: 2.9). 06/2007; 44(12):3267-70. DOI:10.1016/j.molimm.2006.04.013 pp.3267-70
Source: PubMed

ABSTRACT L-ficolin is a pattern-recognition molecule which binds lipoteichoic acid and Gram-positive bacteria and activates the lectin pathway of complement. Five common functional polymorphisms have recently been identified in the FCN2 gene which encodes L-ficolin: three promoter polymorphisms (at positions -986, -602 and -4) which affect serum L-ficolin concentration, and two non-synonymous polymorphisms (Thr236Met and Ala258Ser) which influence carbohydrate binding. We studied the frequencies of these polymorphisms in individuals with invasive pneumococcal disease (IPD) and a control group. Although the five FCN2 polymorphisms were each present in the UK Caucasian population studied, no significant associations were observed between the FCN2 polymorphisms and susceptibility to IPD. This is in contrast to mannose-binding lectin deficiency, which we have previously shown to be associated with increased susceptibility to IPD. Although we are unable to exclude small effects of FCN2 genetic variation on susceptibility to IPD, the result suggests that L-ficolin may not be critical for host defence against pneumococcal infection.

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Keywords

affect serum L-ficolin concentration
 
binds lipoteichoic acid
 
common functional polymorphisms
 
encodes L-ficolin
 
FCN2 gene
 
FCN2 genetic variation
 
FCN2 polymorphisms
 
five FCN2 polymorphisms
 
host defence
 
influence carbohydrate binding
 
invasive pneumococcal disease
 
IPD
 
mannose-binding lectin deficiency
 
non-synonymous polymorphisms
 
pneumococcal infection
 
positions -986
 
promoter polymorphisms
 
significant associations
 
small effects
 
UK Caucasian population