Marburg I mutant of factor VII activating protease (FSAP) as risk factor for arterial thrombosis

1. An isolated coagulation factor VII-activating protease (FSAP) mutant derived from a human donor, which is an atherothrombosis risk factor, and which comprises a Gly to Glu exchange at amino acid position 534 of the FSAP proenzyme sequence, said amino acid sequence position defined according to the proenzyme amino acid sequence of SEQ ID NO:5.

2. The risk factor as claimed in claim 1 , wherein the FSAP mutant further comprises a Glu to Gin exchange at amino acid position 393 of the proenzyme sequence, said amino acid sequence position defined according to the proenzyme amino acid sequence of SEQ ID NO:5.

3. The risk factor as claimed in claim 1 , wherein the FSAP mutant is encoded by a proenzyme nucleotide sequence comprising a G to A base exchange at position 1601, said nucleotide sequence position defined according to the proenzyme nucleotide sequence of SEQ ID NO:1.

4. The risk factor as claimed in claim 3 , wherein the FSAP mutant is encoded by a proenzyme nucleotide sequence further comprising a G to C base exchange at position 1177, said nucleotide sequence position defined according to the proenzyme nucleotide sequence of SEQ ID NO:1.

5. The risk factor as claimed in claim 1 , wherein the FSAP mutant has partially or completely lost the ability to activate single-chain plasminogen activators, as compared with wild-type FSAP.

6. The risk factor as claimed in claim 1 , wherein the FSAP mutant has partially or completely lost the ability to activate prourokinase, as compared with wild-type FSAP.

7. The risk factor as claimed in claim 1 , which indicates a genetic predisposition to the development of atherosclerotic disorders and their sequelae, or thrombotic disorders and their sequelae.

8. The risk factor as claimed in claim 7 , which indicates a genetic predisposition to the development of at least one of arterial and venous occlusive disorders.

9. The risk factor as claimed in claim 7 , which indicates a genetic predisposition to the development of at least one of atherosclerotic and thrombotic restrictions of organ functions.

10. The risk factor as claimed in claim 7 , which indicates a genetic predisposition to the development of one or more of angina pectoris, myocardial infarction, and strokes.

11. The atherothrombosis risk factor as claimed in claim 1 , wherein the ability to activate single-chain plasminogen activators, measured in at least one of whole blood and blood plasma, is reduced as compared with wild-type FSAP.

12. The atherothrombosis risk factor as claimed in claim 1 , wherein the ability to activate prourokinase, measured in at least one of whole blood and blood plasma, is reduced as compared with wild-type FSAP.

13. A diagnostic method for identifying the atherothrombosis risk factor as claimed in claim 1 , which comprises:

(a) determining FSAP prourokinase activating activity in one or more body fluids of an individual;

(b) comparing said FSAP prourokinase activating activity in one or more body fluids of an individual to FSAP prourokinase activating activity in a standard comprising wild-type FSAP;

(c) identifying a reduced FSAP prourokinase activating activity in said one or more body fluids of the individual compared to the FSAP prourokinase activating activity in said standard; and

(d) analyzing at least one of genomic DNA, mRNA, or cDNA of the individual with the reduced FSAP prourokinase activating activity to detect the presence of a heterozygous or homozygous mutation in the FSAP nucleotide sequence, said mutation comprising a G to A base exchange at nucleotide position 1601, said nucleotide sequence position defined according to the proenzyme nucleotide wherein the presence of said mutation identifies the atherothrombosis risk factor sequence of SEQ ID NO:1.

14. The diagnostic method as claimed in claim 13 , further comprising determining the FSAP protein concentration in said one or more body fluids of the individual, and calculating the ratio between said FSAP protein concentration and FSAP prourokinase activating activity in said one or more body fluids.

15. The diagnostic method as claimed in claim 13 , wherein the one or more body fluids comprise blood plasma.

16. The diagnostic method as claimed in claim 13 , further comprising determining the activation of single-chain tissue plasminogen activators in one or more body fluids of the individual.

17. The diagnostic method as claimed in claim 13 , further comprising analyzing at least one of the genomic DNA, mRNA, or cDNA of the individual to detect the presence of a heterozygous or homozygous mutation in the FSAP nucleotide sequence, said mutation comprising a G to C base exchange at nucleotide position 1177, said nucleotide sequence position defined according to the proenzyme nucleotide sequence of SEQ ID NO:1.

18. The diagnostic method as claimed in claim 13 , wherein the FSAP prourokinase activating activity is measured by:

(a) incubating said one or more body fluids of the individual on a solid support to immobilize FSAP on said solid support;

(b) washing the support; and

(c) incubating the FSAP immobilized on the support with reagents which allow determination of the prourokinase activating activity of the FSAP immobilized on the support.

19. The risk factor as claimed in claim 3 , wherein the FSAP mutant is encoded by a proenzyme nucleotide sequence further comprising a base exchange at position 183 which does not lead to an amino acid exchange, said nucleotide sequence position defined according to the proenzyme nucleotide sequence of SEQ ID NO:1.

20. The risk factor as claimed in claim 3 , wherein the FSAP mutant is encoded by a proenzyme nucleotide sequence further comprising a base exchange at position 957 which does not lead to an amino acid exchange, said nucleotide sequence position defined according to the proenzyme nucleotide sequence of SEQ ID NO:1.