vitamin-k-semiquinone-radical and Blood-Coagulation-Disorders--Inherited

Rare bleeding disorders (RBDs), including factor (F) I, FII, FV, FVII, combined FV and FVIII (CF5F8), FXI, FXIII and vitamin-K dependent coagulation factors (VKCF) deficiencies, are a heterogeneous group of hemorrhagic disorder with a variable bleeding tendency. RBDs are due to mutation in underlying coagulation factors genes, except for CF5F8 and VKCF deficiencies. FVII deficiency is the most common RBD with >330 variants in the F7 gene, while only 63 variants have been identified in the F2 gene. Most detected variants in the affected genes are missense (>50% of all RBDs), while large deletions are the rarest, having been reported in FVII, FX, FXI and FXIII deficiencies. Most were located in the catalytic and activated domains of FXI, FX, FXIII and prothrombin deficiencies. Understanding the proper molecular basis of RBDs not only can help achieve a timely and cost-effective diagnosis, but also can help to phenotype properties of the disorders.

Topics: Blood Coagulation Disorders; Blood Coagulation Disorders, Inherited; Blood Coagulation Factors; Coagulation Protein Disorders; Hemorrhage; Hemorrhagic Disorders; Humans; Vitamin K

Gamma-carboxylation, performed by gamma-glutamyl carboxylase (GGCX), is an enzymatic process essential for activating vitamin K-dependent proteins (VKDP) with important functions in various biological processes. Mutations in the encoding

Topics: Blood Coagulation Disorders, Inherited; Carbon-Carbon Ligases; Congenital Abnormalities; Eye; Gene Knockout Techniques; Genetic Association Studies; Genetic Counseling; Genetic Predisposition to Disease; Genotype; Humans; Mutation; Phenotype; Polymorphism, Single Nucleotide; Protein Interaction Domains and Motifs; Skin; Vitamin K

Hereditary combined vitamin K-dependent clotting factors deficiency (VKCFD) is a rare congenital bleeding disorder resulting from variably decreased levels of coagulation factors II, VII, IX and X as well as natural anticoagulants protein C, protein S and protein Z. The spectrum of bleeding symptoms ranges from mild to severe with onset in the neonatal period in severe cases. The bleeding symptoms are often life-threatening, occur both spontaneously and in a surgical setting, and usually involve the skin and mucosae. A range of non-haemostatic symptoms are often present, including developmental and skeletal anomalies. VKCFD is an autosomal recessive disorder caused by mutations in the genes of either gamma-glutamyl carboxylase or vitamin K2,3-epoxide reductase complex. These two proteins are necessary for gamma-carboxylation, a post-synthetic modification that allows coagulation proteins to display their proper function. The developmental and skeletal anomalies seen in VKCFD are the result of defective gamma-carboxylation of a number of non-haemostatic proteins. Diagnostic differentiation from other conditions, both congenital and acquired, is mandatory and genotype analysis is needed to confirm the defect. Vitamin K administration is the mainstay of therapy in VKCFD, with plasma supplementation during surgery or severe bleeding episodes. In addition, prothrombin complex concentrates and combination therapy with recombinant activated FVII and vitamin K supplementation may constitute alternative treatment options. The overall prognosis is good and with the availability of several effective therapeutic options, VKCFD has only a small impact on the quality of life of affected patients.

Topics: Blood Coagulation Disorders, Inherited; Blood Coagulation Factors; Blood Proteins; Carbon-Carbon Ligases; Humans; Infant, Newborn; Protein C; Protein S; Recombinant Proteins; Vitamin K; Vitamin K Deficiency

γ-glutamyl carboxylase (GGCX), also known as vitamin K-dependent glutamyl carboxylase, catalyzes the posttranslational modification of specific glutamate residues in vitamin K-dependent proteins (VKDPs), and participates multiple biological functions including blood coagulation, bone metabolism, vascular calcification, and cell proliferation. It has been reported originally that GGCX pathogenic variation causes blood coagulation deficiency, which is called as vitamin K-dependent coagulation factor deficiency 1 (VKCFD1). Recently, it has been found that GGCX gene variation results in multiple clinical phenotypes, including dermatological, ophthalmological, skeletal or cardiac abnormalities. Among them, dermatological phenotype is the most common, which is known as pseudoxanthoma elasticum-like syndrome. This paper has reviewed the GGCX pathogenic variation associated phenotypes, in order to increase the recognition of GGCX-related genetic diseases and to help its diagnosis and treatment.

Topics: Blood Coagulation Disorders, Inherited; Carbon-Carbon Ligases; Carboxy-Lyases; Humans; Phenotype; Vitamin K; Vitamin K 1

Combined deficiency of the vitamin K-dependent clotting factors (VKCFD) is a rare bleeding disorder involving defective gamma-carboxylation of coagulation factors II , VII, IX and X as well as natural anticoagulants protein C and protein S. The disease is characterized by a cluster of different, often life threatening, bleeding symptoms occurring both spontaneously and in a surgical setting. In the present paper we describe two different treatment modalities to be used both in a programmed surgical procedure and in an emergency scenario. As this disease is a natural model that resembles oral anticoagulation, our experience discloses a possible rationale in the use of recombinant activated FVII for warfarin reversal.

Topics: Adult; Biopsy; Blood Coagulation Disorders, Inherited; Blood Coagulation Tests; Blood Loss, Surgical; Factor VII; Factor VII Deficiency; Factor VIIa; Female; Gastroscopy; Hemostasis, Surgical; Homozygote; Humans; Mixed Function Oxygenases; Recombinant Proteins; Tooth Extraction; Vitamin K; Vitamin K Epoxide Reductases

Hereditary combined vitamin K-dependent (VKD) coagulation factor deficiency is an autosomal recessive bleeding disorder associated with defects in either the gamma-carboxylase, which carboxylates VKD proteins to render them active, or the vitamin K epoxide reductase (VKORC1), which supplies the reduced vitamin K cofactor required for carboxylation. Such deficiencies are rare, and we report the fourth case resulting from mutations in the carboxylase gene, identified in a Tunisian girl who exhibited impaired function in hemostatic VKD factors that was not restored by vitamin K administration. Sequence analysis of the proposita did not identify any mutations in the VKORC1 gene but, remarkably, revealed 3 heterozygous mutations in the carboxylase gene that caused the substitutions Asp31Asn, Trp157Arg, and Thr591Lys. None of these mutations have previously been reported. Family analysis showed that Asp31Asn and Thr591Lys were coallelic and maternally transmitted while Trp157Arg was transmitted by the father, and a genomic screen of 100 healthy individuals ruled out frequent polymorphisms. Mutational analysis indicated wild-type activity for the Asp31Asn carboxylase. In contrast, the respective Trp157Arg and Thr591Lys activities were 8% and 0% that of wild-type carboxylase, and their compound heterozygosity can therefore account for functional VKD factor deficiency. The implications for carboxylase mechanism are discussed.

Topics: Alleles; Amino Acid Sequence; Amino Acid Substitution; Base Sequence; Blood Coagulation Disorders, Inherited; Carbon-Carbon Ligases; Child; Coagulation Protein Disorders; Conserved Sequence; DNA Mutational Analysis; DNA Primers; Evolution, Molecular; Female; Heterozygote; Humans; Infant; Male; Mixed Function Oxygenases; Molecular Sequence Data; Mutation, Missense; Pedigree; Polymerase Chain Reaction; Sequence Homology, Amino Acid; Vitamin K; Vitamin K Epoxide Reductases