Disease relevance of Hemophilia B

• Hemophilia B, also known as Christmas disease, arises from mutations in the factor IX (F9) gene [1].
• An X-chromosomal predisposing locus to manic-depressive illness has been suggested since 1969 on the basis of the cosegregation of this trait in some families with phenotypic markers, such as color blindness, the glucose-6-phosphate dehydrogenase deficiency, and the coagulation factor IX deficiency [2].
• We have used molecular conjugates containing combinations of DNA, adenovirus, polylysine, and transferrin to transfect primary cells derived from canines with hemophilia B (factor IX deficiency), as well as a canine epithelial cell line [3].
• They included 62 haemophiliacs 32 patients with von Willebrand's disease (VWD), 9 with Christmas disease (CD), 6 with afibrinogenemia, 1 with prothrombin deficiency, and 6 were thought to have platelet dysfunction [4].
• Hypercalcemia associated with normal 1,25-dihydroxyvitamin D concentrations in a neonate with factor IX deficiency [5].

High impact information on Hemophilia B

• DXS102 is close to the hemophilia-B locus (z[theta] = 13.6 at theta = .02) and might thus be used as an alternative probe for diagnosis in Hemophila-B families not informative for intragenic RFLPs [6].
• We report a quantitative protein C deficiency combined with a factor IX deficiency in a one-year-old boy [7].
• Characterization of the original Christmas disease mutation (cysteine 206----serine): from clinical recognition to molecular pathogenesis [8].
• Previously, from the plasma of unrelated haemophilia-B patients, we isolated two non-functional Factor IX variants, namely Los Angeles (IXLA) and Long Beach (IXLB) [9].
• Prevention of a secondary response to factor IX by cyclophosphamide was attempted in an 11 year old patient with severe Christmas disease [10].

Chemical compound and disease context of Hemophilia B

• Re: tranexamic acid and bleeding: a double-blind cross-over study on three brothers with Christmas disease (factor IX deficiency) [11].
• Acute hepatitis in a patient with mild factor IX deficiency after anesthesia with isoflurane [12].
• This contrasts with a previously reported case in which both thyroxine and cortisone were required for complete correction of the factor IX deficiency [13].
• Specific disorders covered are clotting factor deficiencies, hemophilia A, factor VIII inhibitors, von Willebrand disease, hemophilia B (Christmas disease), other congenital coagulation disorders, acquired deficiency of factors II, VII, IX and X, and defibrination syndrome [14].

Gene context of Hemophilia B

• An identifiable coagulopathy was detected in nine patients (protein C deficiency in six, protein S deficiency in two, and factor IX deficiency treated with factor IX concentrate in one) [15].
• Liver dysfunction and exposure to the hepatitis B antigen were assessed by serum transaminase (SGPT and SGOT) levels and HBsAg and anti-HBs during a three year period in a group of 118 patients with factor VIII or factor IX deficiency [16].
• When coagulation is triggered with the high thromboplastin concentrations normally used in clinical routine tests, the generation of thrombin activity in plasma of patients with congenital factor IX deficiency before and after reconstitution with purified factor IX appears identical [17].
• Hemophilia B or Christmas disease is an X-linked condition caused by absent or reduced levels of functional coagulation factor IX [18].

Analytical, diagnostic and therapeutic context of Hemophilia B

• Following transplantation, Factor IX levels rapidly normalised and have remained so, representing a phenotypic cure of his Christmas disease [19].

References