A novel, possibly functional, single nucleotide polymorphism in the coding region of the thrombin-activatable fibrinolysis inhibitor (TAFI) gene is also associated with TAFI levels [7]

In a recent issue of Blood, Henry et al reported the identification of several single nucleotide polymorphisms (SNPs) in the promoter and 39 untranslated region of the thrombin-activatable fibrinolysis inhibitor (TAFI) gene. They also investigated the 505A/G SNP in the coding region of the TAFI gene resulting in an amino acid (aa) substitution, Thr147Ala. Henry et al showed that plasma TAFI antigen (Ag) levels are strongly associated with all these SNPs that turned out to be in strong linkage disequilibrium. This association confirmed and extended preliminary reports on the association of TAFI plasma levels and SNPs in the TAFI gene promoter.
We identified another SNP, 1040C/T, in the coding region of the TAFI gene by comparing published sequences. This SNP also results in an aa substitution (Thr325Ile). This SNP is of particular interest because it has been shown that the presence of an Ile325 residue has a positive influence on both TAFIa activity and stability in vitro resulting in increased antifibrinolytic activity.5 On the contrary, the Thr147Ala substitution has no effect on the functional properties of TAFI in vitro.
We determined in a group of 152 blood donors the genotype frequency and allele frequency of the 1040C/T SNP and correlated this with TAFI Ag levels. [...]