Hereditary factor IX deficiency disease, Christmas disease
Type of disease: Rare conditions
Hemophilia B is a bleeding disorder that slows the blood clotting process. People with this disorder experience prolonged bleeding or oozing following an injury or surgery. In severe cases of hemophilia, heavy bleeding occurs after minor trauma or even in the absence of injury. Serious complications can result from bleeding into the joints, muscles, brain, or other internal organs. Milder forms may not become apparent until abnormal bleeding occurs following surgery or a serious injury. People with an unusual form of hemophilia B, known as hemophilia B Leyden, experience episodes of excessive bleeding in childhood but have few bleeding problems after puberty. Hemophilia B is inherited in an X-linked recessive pattern and is caused by mutations in the F9 gene.Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.