Thrombosis's risk according taking drugs hormonal contraception (F II, F V)

DNA test is based on the simultaneous determination of the status of F2 and F5 genes (clotting factors) as the main markers of genetic predisposition to blood clotting (thrombus formation).

• The role of the FII gene (blood coagulation factor II, prothrombin).
  • It has been proven that polymorphism 20210 G/A of the F2 gene leads to an increase in the production of prothrombin, one of the proteins that triggers the blood clotting process. The mutation is inherited in an autosomal dominant type, i.e. thrombophilia occurs even in a heterozygous carrier of the altered gene (G/A). The presence of the 20210A allele by 3 or more times, and against the background of smoking − by 40 or more times increases the risk of venous thrombosis, including thrombosis of the vessels of the brain and heart, especially at a young age. Carriers of the G/A genotype have a 4-5-fold increased risk of early myocardial infarction (under the age of 45-50 years). There is also an increased risk of thromboembolism after surgical interventions and against the background of taking oral contraceptives (the relative risk of thrombophilia and venous thromboembolism in heterozygous carriers of 20210 G/A polymorphism increases 16 times). The G/A prothrombin genotype is also a risk factor for pregnancy complications (fetoplacental insufficiency, miscarriage, intrauterine fetus death, toxicosis, fetal retardation, and placental abruption).
• The role of the F5 gene.
  • The 1691 G/A substitution of the F5 gene (“Leiden mutation”) leads to a change in the structure of the proaxelerin (clotting factor V) protein, increasing the stability of its active form. Clinically, this is manifested by recurrent venous thrombosis and thromboembolism. The presence of polymorphism in a homozygous or heterozygous form by 3 or more times, and against the background of hormone replacement therapy or oral contraceptives − by 30 or more times increases the risk of venous thrombosis. The risk of myocardial infarction increases by 2 or more times, the risk of developing pregnancy pathology (termination of pregnancy, preeclampsia, chronic placental insufficiency and fetus growth retardation syndrome) increases by 3 or more times. Also, patients who are both carriers of the 20210 G/A polymorphism of the prothrombin F2 gene and the “Leiden mutation” are at even greater risk of developing thrombosis and thromboembolism.
• The presence in the anamnesis:
  • Thrombosis
  • Thromboembolism
  • Preeclampsia
  • Thromboembolic complications during pregnancy
  • Ischemic stroke
  • The risk of thromboembolic complications when taking oral contraceptives and hormone replacement therapy

For these genes, there is no concept of "norms" and "pathologies", because gene polymorphisms are being investigated. The interpretation of the results of the analysis should be carried out by the attending physician, taking into account the medical history, the results of other genetic analysis, clinical manifestations and laboratory data.

Possible genotypes of the F2 gene (locus 20210 G/A)

• G/G is not associated with the risk of developing diseases;
• G/A is a genotype predisposing to increased blood clotting, in a heterozygous form. The risks of thrombosis and thromboembolism increase by 7 times. The risk of obstetric and gynecological complications increases;
• A/A is a genotype predisposing to increased blood clotting, in a homozygous form. The risks of thrombosis and thromboembolism increase by 20 times. The risk of obstetric and gynecological complications increases.

Possible genotypes of the F5 gene (locus 1691 G/A)

• G/G is not associated with the risk of developing diseases;
• G/A is a genotype predisposing to increased blood clotting, in a heterozygous form. the risks of thrombosis and thromboembolism increase by 7 times. The risk of obstetric and gynecological complications increases.
• A/A is a genotype predisposing to increased blood clotting, in a homozygous form. The risks of thrombosis and thromboembolism increase by 20 times. The risk of obstetric and gynecological complications increases.