Hemostasis, genetics of

Inherited factors that play a role in hemostasis, the stoppage of blood flow through a blood vessel. There is genetic regulation of proteins involved in hemostasis and atherothrombotic disorders, including myocardial infarction and stroke. People with a family history of coronary heart disease, for example, are more likely to develop the disease themselves, indicating that genetic factors may be important in this form of unwanted hemostasis. Genetic factors contribute at least about half of the known variation in the concentrations of hemostatic factors (such as fibrinogen, factor VII, factor VIII, PAI-1, tissue plasminogen activator, factor XIIa, factor XIII A-subunit and B-subunit, and von Willebrand factor). The rest of the variation is due to environmental factors. (Ref.: Lancet 2001; 357: 101-05.)