Ficolin-2 levels and FCN2 haplotypes influence hepatitis B infection outcome in Vietnamese patients

PLoS One. 2011;6(11):e28113. doi: 10.1371/journal.pone.0028113. Epub 2011 Nov 22.


Human Ficolin-2 (L-ficolins) encoded by FCN2 gene is a soluble serum protein that plays an important role in innate immunity and is mainly expressed in the liver. Ficolin-2 serum levels and FCN2 single nucleotide polymorphisms were associated to several infectious diseases. We initially screened the complete FCN2 gene in 48 healthy individuals of Vietnamese ethnicity. We genotyped a Vietnamese cohort comprising of 423 clinically classified hepatitis B virus patients and 303 controls for functional single nucleotide polymorphisms in the promoter region (-986G>A, -602G>A, -4A>G) and in exon 8 (+6424G>T) by real-time PCR and investigated the contribution of FCN2 genotypes and haplotypes to serum Ficolin-2 levels, viral load and liver enzyme levels. Haplotypes differed significantly between patients and controls (P = 0.002) and the haplotype AGGG was found frequently in controls in comparison to patients with hepatitis B virus and hepatocellular carcinoma (P = 0.0002 and P<0.0001) conferring a protective effect. Ficolin-2 levels differed significantly between patients and controls (p<0.0001). Patients with acute hepatitis B had higher serum Ficolin-2 levels compared to other patient groups and controls.The viral load was observed to be significantly distributed among the haplotypes (P = 0.04) and the AAAG haplotype contributed to higher Ficolin-2 levels and to viral load. Four novel single nucleotide polymorphisms in introns (-941G>T, -310G>A, +2363G>A, +4882G>A) and one synonymous mutation in exon 8 (+6485G>T) was observed. Strong linkage was found between the variant -986G>A and -4A>G. The very first study on Vietnamese cohort associates both Ficolin-2 serum levels and FCN2 haplotypes to hepatitis B virus infection and subsequent disease progression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Case-Control Studies
  • Female
  • Genetic Predisposition to Disease*
  • Haplotypes / genetics*
  • Hepatitis B / blood
  • Hepatitis B / genetics*
  • Hepatitis B / virology*
  • Hepatitis B virus / physiology*
  • Humans
  • Lectins / blood*
  • Lectins / genetics*
  • Linkage Disequilibrium / genetics
  • Male
  • Middle Aged
  • Polymorphism, Single Nucleotide / genetics
  • Vietnam
  • Viral Load / genetics
  • Young Adult


  • Lectins
  • ficolin