Biomaterial Database

Haemophilia B in a female caused by skewed inactivation of the normal X-chromosome. 2000

C Espinós, and J I Lorenzo, and P Casaña, and F Martínez, and J A Aznar

Unidad de Coagulopatías Congénitas, Hospital Universitario La Fe. Avd. de Campanar, 21. 46009 Valencia, Spain. espinos@uv.es

Hemophilia B (factor IX deficiency) is an X-linked recessive disorder with a prevalence of 1:30,000 male births, which rarely affects females. A missense mutation T38R (6488C>G) of the factor IX (FIX) gene was characterized in a young female with moderate-to-severe hemophilia B. She is heterozygous for this mutation, which she inherited from her carrier mother. Analysis of the methyl-sensitive HpaII sites in the first exon of the human androgen-receptor locus indicated a de novo skewed X-chromosomal inactivation. This indicates that the paternal X-chromosome carrying her normal FIX gene is the inactive one, which has led to the phenotypic expression of hemophilia B in this patient.

UI	MeSH Term	Description	Entries
D007223	Infant	A child between 1 and 23 months of age.	Infants
D008297	Male		Males
D010375	Pedigree	The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.	Family Tree,Genealogical Tree,Genealogic Tree,Genetic Identity,Identity, Genetic,Family Trees,Genealogic Trees,Genealogical Trees,Genetic Identities,Identities, Genetic,Tree, Family,Tree, Genealogic,Tree, Genealogical,Trees, Family,Trees, Genealogic,Trees, Genealogical
D011516	Prothrombin	A plasma protein that is the inactive precursor of thrombin. It is converted to thrombin by a prothrombin activator complex consisting of factor Xa, factor V, phospholipid, and calcium ions. Deficiency of prothrombin leads to hypoprothrombinemia.	Coagulation Factor II,Factor II,Blood Coagulation Factor II,Differentiation Reversal Factor,Factor II, Coagulation,Factor, Differentiation Reversal,II, Coagulation Factor
D011658	Pulmonary Fibrosis	A process in which normal lung tissues are progressively replaced by FIBROBLASTS and COLLAGEN causing an irreversible loss of the ability to transfer oxygen into the bloodstream via PULMONARY ALVEOLI. Patients show progressive DYSPNEA finally resulting in death.	Alveolitis, Fibrosing,Idiopathic Diffuse Interstitial Pulmonary Fibrosis,Fibroses, Pulmonary,Fibrosis, Pulmonary,Pulmonary Fibroses,Alveolitides, Fibrosing,Fibrosing Alveolitides,Fibrosing Alveolitis
D002836	Hemophilia B	A deficiency of blood coagulation factor IX inherited as an X-linked disorder. (Also known as Christmas Disease, after the first patient studied in detail, not the holy day.) Historical and clinical features resemble those in classic hemophilia (HEMOPHILIA A), but patients present with fewer symptoms. Severity of bleeding is usually similar in members of a single family. Many patients are asymptomatic until the hemostatic system is stressed by surgery or trauma. Treatment is similar to that for hemophilia A. (From Cecil Textbook of Medicine, 19th ed, p1008)	Christmas Disease,Factor IX Deficiency,Deficiency, Factor IX,F9 Deficiency,Haemophilia B,Hemophilia B Leyden,Hemophilia B(M),Plasma Thromboplastin Component Deficiency,Bs, Hemophilia,Deficiencies, F9,Deficiencies, Factor IX,Deficiency, F9,Disease, Christmas,F9 Deficiencies,Factor IX Deficiencies,Haemophilia Bs,Hemophilia Bs,Hemophilia Bs (M)
D004303	Dosage Compensation, Genetic	Genetic mechanisms that allow GENES to be expressed at a similar level irrespective of their GENE DOSAGE. This term is usually used in discussing genes that lie on the SEX CHROMOSOMES. Because the sex chromosomes are only partially homologous, there is a different copy number, i.e., dosage, of these genes in males vs. females. In DROSOPHILA, dosage compensation is accomplished by hypertranscription of genes located on the X CHROMOSOME. In mammals, dosage compensation of X chromosome genes is accomplished by random X CHROMOSOME INACTIVATION of one of the two X chromosomes in the female.	Dosage Compensation (Genetics),Gene Dosage Compensation,Hypertranscription, X-Chromosome,X-Chromosome Hypertranscription,Compensation, Dosage (Genetics),Compensation, Gene Dosage,Compensation, Genetic Dosage,Dosage Compensation, Gene,Gene Dosage Compensations,Genetic Dosage Compensation,Genetic Dosage Compensations,Hypertranscription, X Chromosome,X Chromosome Hypertranscription
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D016040	Lung Transplantation	The transference of either one or both of the lungs from one human or animal to another.	Grafting, Lung,Transplantation, Lung,Graftings, Lung,Lung Grafting,Lung Graftings,Lung Transplantations,Transplantations, Lung