Summary
An increased erythrocyte aggregation (EA) is associated with capillary slow flow,
tissue hypoxemia and endothelial dysfunction. Fibrinogen is a major determinant in
the formation of aggregated red blood cells. It has been suggested that the Bβ-fibrinogen
–455G/A polymorphism is associated with erythrocyte hyperaggregability in men with
coronary artery disease.The purpose of this study was to investigate the influence
of the β-fibrinogen –455G/A polymorphism on erythrocyte aggregation in apparently
healthy individuals. Plasma fibrinogen, red blood cell count, serum lipids, erythrocyte
sedimentation rate, and the genotype of the Bβ-fibrinogen –455G/A polymorphism were
examined in a cohort of 545 apparently healthy individuals and those with atherothrombotic
risk factors. A whole blood erythrocyte aggregation test was performed by using a
simple slide test and image analysis. In men, EA levels and plasma fibrinogen levels
were significantly higher in subjects carrying the –455A allele compared to subjects
with the –455 GG genotype.This association did not exist in women carrying the fibrinogen
–455A allele.The –455GA/AA men presented significantly higher correlation between
the plasma fibrinogen concentrations and EA. This observation raises the prospect
of possible change in the functional properties of the –455GA/AA fibrinogen, enhancing
its ability to induce EH. This study suggests that the Bβ-fibrinogen –455A allele
is related to EH in men only. Putative mechanism could be hyperfibrinogenemia anda
functional change in the fibrinogen molecule that alters its ability to interact with
red blood cells and supports the aggregability of these cells.
Keywords
Erythrocyte aggregation - fibrinogen - gene polymorphism