Summary
A genetic polymorphism (Arg/Gln353) of coagulation factor VII was recently identified and shown to be associated with
differences in basal factor VII coagulant activity. Postprandial lipaemia seems to
exert an acute but evanescent effect on the activity of factor VII, and the influence
of the Arg/Gln353 polymorphism on factor VII activation during postprandial lipaemia was therefore
studied in male post-infarction patients [age 48.8 ± 3.3 years (mean ± SD)] with Arg/Arg
(n = 23) and Arg/Gln (n = 8) genotypes. Factor VII antigen (VIlag) and activity along
with plasma lipoproteins were determined before and after intake of a mixed meal-type
of oral fat load. Patients with the Arg/Gln genotype had basal VIlag and activated
factor VII (Vila) levels 75% and 48%, respectively, of those of patients homozygous
for the Arg allele. In absolute terms, Vila increased more in homozygotes for the
Arg allele (AO-6 h Vila 1.76 ± 1.48 ng/ml) than in heterozygotes (0.60 ± 0.27 ng/ml)
in response to fat intake, but the percentage increase in Vila molecules did not differ
significantly between subjects with Arg/Arg and Arg/Gln genotypes (37 ± 32% versus
27 ± 15%). This suggests that the influence of the Arg/Gln polymorphism on factor
VII activity is mainly accounted for by differences in the basal factor VII protein
level between genotypes. Since most of our lives are spent in the postprandial state,
possession of the factor VII-Gln353 allele is likely to confer protection against coronary heart disease by reducing
the amount of Vila produced in response to fat intake.
