title: Different outcome of six homozygotes for prothrombin A20210A gene variant.
abstract: Prothrombin G20210A gene variant (FII G20210A) is a risk factor for venous thrombotic disease while conflicting results have been reported for the risk of arterial thrombotic events. However, vascular episodes were absent in up to 40% of the 67 homozygotes for the G20210A described so far, which indicates that the clinical expression depends on additional risk/trigger factors. We describe six homozygotes for the G20210A variant, among which the first pair of siblings (cases n. 3 and 4) reported so far that displayed a strongly heterogeneous clinical outcome. Case 1, a female of 27 years, developed a full thrombosis of common femoral, superficial and popliteal veins. She assumed oral contraceptives in the last two years. Case n. 2, 34 years old, suffered of recurrent pregnancy loss in absence of any causative alteration. Cases n. 3 and n. 5 experienced arterial thrombotic disease, i.e., juvenile myocardial infarction (40 years old) and stroke (48 years old), respectively, in absence of other risk factors. Finally, cases n. 4 and 6 identified as homozygotes for the FII G20210A variant being consanguineous of symptomatic subjects bearing the variant, did not experience any episode of venous nor arterial disease. Both of them have chronic liver disease with an impairement of the prothrombin time INR. Thus, homozygotes for the G20210A are at risk for arterial (in addition to venous) thromobotic events; chronic liver disease might modulate this risk.
authors.affiliation: Department of Internal Medicine, Fatebenefratelli Hospital of Naples, Naples, Italy. pdimicco@libero.it
authors.forename: Pierpaolo
authors.initials: P
authors.lastname: Di Micco
authors.forename: Rosanna
authors.initials: R
authors.lastname: Di Fiore
authors.forename: Alferio
authors.initials: A
authors.lastname: Niglio
authors.forename: Sandro
authors.initials: S
authors.lastname: Quaranta
authors.forename: Antonella
authors.initials: A
authors.lastname: Angiolillo
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Cardillo
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Castaldo
mesh_terms: D000328:Adult; D000925:Anticoagulants / Q000627:therapeutic use; D005260:Female; D005268:Femoral Vein / Q000000981:diagnostic imaging; D005500:Follow-Up Studies; D014644:Genetic Variation; D006720:Homozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D011152:Popliteal Vein / Q000000981:diagnostic imaging; D011516:Prothrombin / Q000235:genetics*; D035781:Siblings; D013788:Thalamus / Q000000981:diagnostic imaging; D013997:Time Factors; D016896:Treatment Outcome; D014463:Ultrasonography; D020246:Venous Thrombosis / Q000000981:diagnostic imaging
chemical_list: D000925:Anticoagulants; D011516:Prothrombin