BACKGROUND: Previously, we found increased clot-lysis time (CLT), as measured with a plasma-based assay, to increase the risk of venous thrombosis in two population-based case-control studies. The genes influencing CLT are as yet unknown. PATIENTS/ METHODS: We tested CLT as risk factor for venous thrombosis in Kindred Vermont II (n = 346), a pedigree suffering from a high thrombosis risk, partially attributable to a type I protein C deficiency. Furthermore, we tested for quantitative trait loci (QTLs) for CLT, using variance component linkage analysis. RESULTS: Protein C-deficient family members had shorter CLTs than non-deficient members (median CLT 67 min vs. 75 min). One standard deviation increase in CLT increased the risk of venous thrombosis 2.4-fold in non-deficient family members. Protein C deficiency without elevated CLT increased the risk 6.9-fold. Combining both risk factors yielded a 27.8-fold increased risk. The heritability of CLT was 42-52%. We found suggestive evidence of linkage on chromosome 11 (62 cM), partly explained by the prothrombin 20210A mutation, and on chromosome 13 (52 cM). Thrombin-activatable fibrinolysis inhibitor genotypes did not explain the variation in CLT. CONCLUSION: Hypofibrinolysis appears to increase thrombosis risk in this family, especially in combination with protein C deficiency. Protein C deficiency is associated with short CLT. CLT is partly genetically regulated. Suggestive QTLs were found on chromosomes 11 and 13.
BACKGROUND: Previously, we found increased clot-lysis time (CLT), as measured with a plasma-based assay, to increase the risk of venous thrombosis in two population-based case-control studies. The genes influencing CLT are as yet unknown. PATIENTS/ METHODS: We tested CLT as risk factor for venous thrombosis in Kindred Vermont II (n = 346), a pedigree suffering from a high thrombosis risk, partially attributable to a type I protein C deficiency. Furthermore, we tested for quantitative trait loci (QTLs) for CLT, using variance component linkage analysis. RESULTS: Protein C-deficient family members had shorter CLTs than non-deficient members (median CLT 67 min vs. 75 min). One standard deviation increase in CLT increased the risk of venous thrombosis 2.4-fold in non-deficient family members. Protein C deficiency without elevated CLT increased the risk 6.9-fold. Combining both risk factors yielded a 27.8-fold increased risk. The heritability of CLT was 42-52%. We found suggestive evidence of linkage on chromosome 11 (62 cM), partly explained by the prothrombin 20210A mutation, and on chromosome 13 (52 cM). Thrombin-activatable fibrinolysis inhibitor genotypes did not explain the variation in CLT. CONCLUSION: Hypofibrinolysis appears to increase thrombosis risk in this family, especially in combination with protein C deficiency. Protein C deficiency is associated with short CLT. CLT is partly genetically regulated. Suggestive QTLs were found on chromosomes 11 and 13.
Authors: T Lisman; F W Leebeek; L O Mosnier; B N Bouma; J C Meijers; H L Janssen; H K Nieuwenhuis; P G De Groot Journal: Gastroenterology Date: 2001-07 Impact factor: 22.682
Authors: Mirjam E Meltzer; Ton Lisman; Philip G de Groot; Joost C M Meijers; Saskia le Cessie; Carine J M Doggen; Frits R Rosendaal Journal: Blood Date: 2010-04-12 Impact factor: 22.113
Authors: S J Hasstedt; B T Scott; P W Callas; C Y Vossen; F R Rosendaal; G L Long; E G Bovill Journal: J Thromb Haemost Date: 2004-06 Impact factor: 5.824
Authors: E Y Anteby; C Greenfield; S Natanson-Yaron; D Goldman-Wohl; Y Hamani; V Khudyak; I Ariel; S Yagel Journal: Mol Hum Reprod Date: 2004-03-02 Impact factor: 4.025