No abstract available.
Factor V Deficiency* ; Factor V*

Factor V ; Factor V Deficiency ; Female ; Humans ; Infant, Newborn

OBJECTIVETo identify the phenotype and genotype in four Chinese pedigrees with inherited coagulation factor V (FV) deficiency.

METHODSThe tests of activated partial thromboplastin time (APTT), prothrombin time (PT), FV activity (FV:C) and FV antigen (FV:Ag) were used for phenotype diagnosis. All the exons and exon-intron boundaries of F5 gene were amplified by PCR and analyzed by direct sequencing.

RESULTSThe APTT and PT in each of the four probands were obviously prolonged, and both activity and antigen of FV in the four probands were extremely lower compared with that of normal mixed plasma. Sequencing of F5 gene in proband 1 identified a heterozygous mutation, G16088C (Asp68His), and four polymorphisms, T35788C (Met385Thr), A47295G (His1299Arg), A58668G (Met1736Val) and A74083G (Asp2194Gly), which were located in the same chromosome; proband 2 was homozygous for two mutations, C46253T (Arg952Cys) and C46724T(Gln1109stop); the F5 gene of proband 3 showed a homozygous missense mutation, C67793G(Pro2006Ala); and proband 4 was homozygous for one missense mutation, C74022T (Arg2174Cys).

CONCLUSIONFive mutations (Asp68His, Arg952Cys, Gln1109stop, Pro2006Ala and Arg2174Cys) and four polymorphisms (Met385Thr, His1299Arg, Met1736Val and Asp2194Gly) may lead to type I inherited FV deficiency for these four probands, respectively. Gln1109stop, Pro2006Ala and Arg2174Cys haven't been identified before.

Factor V ; Factor V Deficiency ; Genotype ; Humans ; Pedigree ; Phenotype

A case of Factor V deficiency, the first case in Korea, is reported in a 9-year-old boy whose plasma concentration of Factor V was 6%. He complained of easy bruisability, prolonged bleeding from the mouth after minor trauma and hemarthrosis and flexion contracture of the right knee. His parents are heterozygous (maternal Factor V concentration 52%, paternal 40%).
Child ; Factor V Deficiency/*congenital ; Humans ; Male

OBJECTIVETo investigate the gene defect in a hereditary coagulation factor V (FV) deficiency family.

METHODSThe plasma FV actigen was measured by one-stage clotting assay. The FV antigen was assayed by Biotin-Avidin enzyme linked immunosorbent assay (BA-ELISA). The full length of exon 1 to exon 25 and the 5' untranslated sequence of FV genomic DNA were analyzed by polymerase chain reaction (PCR) and direct sequencing of the amplified fragments, meanwhile the defect was identified by T/A cloning sequencing.

RESULTSThe plasma coagulant activity and amount of FV of the proband were marked deficient (1% and 1.54%, respectively). DNA sequence analysis for the proband revealed a causative mutation in a heterozygous status. It was one base pair deletion in exon 4 at nucleotide 675 inherited from her mother.

CONCLUSIONSA novel mutation in the FV gene was identified in the proband with congenital FV deficiency. The mutation was 675delA in exon 4 resulting in a frameshift and a premature termination codon.

Adolescent ; Blood Coagulation ; Factor V ; analysis ; genetics ; Factor V Deficiency ; blood ; genetics ; Female ; Humans ; Mutation

OBJECTIVE: To explore the molecular basis for a pedigree affected with coagulation factor V (FV) deficiency. METHODS: Clinical data of the patient and his family members was analyzed. Targeted capture and next-generation sequencing (NGS) and Sanger sequencing were carried out to detect potential variant of the FV gene. RESULTS: The patient presented with jaundice and prolonged prothrombin time (PT) and activated partial thromboplastic time (APTT). V factor activity measured only 0.1% of the normal level, though the patient had no sign of bleeding. A paternal heterozygous variant c.653T>C (p.F218S) and a maternal heterozygous variant c.3642_3643del (p.P1215Rfs*175) were identified in the FV gene of the patient. His elder brother was a heterozygous carrier of the c.653T>C (p.F218S) variant. c.653T>C(p.F218S) was a known pathogenic variant, while the c.3642_3643del (p.P1215Rfs*175) variant was unreported previously. CONCLUSION Mutations of the FV gene probably underlie the hereditary coagulation factor V deficiency in this patient. NGS combined with Sanger sequencing has detected potential variant with efficiency and provided a reliable basis for clinical and prenatal diagnosis for this family.
Aged ; Factor V ; Factor V Deficiency ; genetics ; Genetic Variation ; Heterozygote ; Humans ; Male ; Mutation ; Pedigree ; Phenotype

OBJECTIVE: To explore the genetic basis for a consanguineous pedigree affected with inherited coagulation factor V deficiency. METHODS: Genomic DNA was extracted from peripheral blood samples from the pedigree and subjected to next generation sequencing for screening variants of the F5 gene. Suspected pathogenic variant was verified by using Sanger sequencing. Pathogenicity of the variant was evaluated according to ACMG guidelines. RESULTS: A homozygous frameshifting variant, c.4096delC (p.Leu1366Phefs*3), was identified in the F5 gene in the proband, which was confirmed to be derived from her consanguineous parents. This variant was absent in all databases including 10 000 in-house Chinese exome sequences. Based on the ACMG guidelines, the c.4096delC was predicted to be a pathogenic variant. CONCLUSION A novel pathogenic variant has been identified in the F5 gene in a consanguineous pedigree with inherited coagulation factor V deficiency, which has enriched the spectrum of F5 gene variants.
Consanguinity ; Factor V ; genetics ; Factor V Deficiency ; genetics ; Female ; Genetic Variation ; Humans ; Pedigree

Acquired factor V inhibitor is a rare condition with a variety of clinical manifestations that range from no bleeding symptoms to life-threatening hemorrhage or thromboembolic events. Treatment is determined by the clinical course and focuses on controlling the hemorrhagic event and decreasing the antibody titer if bleeding symptoms are present. We report herein a case involving a 70-year-old man who developed acquired factor V inhibitor after antibiotic administration (11-day course of ceftriaxone and successive 5-day course of piperacillin-tazobactam) for pneumonia. His condition was characterized by elevated prothrombin and activated partial thromboplastin times without bleeding events. Coagulation factor assays revealed undetectable factor V activity and a factor V inhibitor level of 3.29 Bethesda units. After cessation of the antibiotics, both the prothrombin and activated partial thromboplastin times gradually normalized.
Aged ; Anti-Bacterial Agents ; Blood Coagulation Factors ; Ceftriaxone ; Factor V Deficiency ; Factor V* ; Hemorrhage ; Humans ; Pneumonia ; Prothrombin ; Thromboplastin

OBJECTIVETo explore the molecular pathogenesis for a pedigree affected with coagulation factor Ⅴ (FⅤ) deficiency.

METHODSProthrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), coagulation factor Ⅱ activity (FⅡ: C), FⅤ activity (FⅤ: C), coagulation factor Ⅶ activity (FⅦ: C), and coagulation factor Ⅹ activity (FⅩ: C) were determined with a STAGO automatic coagulometer. FⅤ antigen (FⅤ: Ag) was detected with enzyme linked immunosorbent assay (ELISA). All exons and their flanking regions, and 5' and 3' untranslated regions of the F5 gene were analyzed by direct sequencing. Suspected mutation was verified by reverse sequencing as well as testing of family members. ClustalX software was used to analyze the conservative property of the mutation sites. PROVEAN and MutationTaster online software was used to predict the effect of the mutation on the protein function. Swiss-pdbViewer was used to analyze the protein model and interaction of amino acids.

RESULTSThe PT and APTT of the proband were slightly prolonged to 15.2 s and 41.8 s, respectively. And the FⅤ: C and FⅤ: Ag measured 55% and 62%, respectively. The FⅤ: C and FⅤ: Ag of his father and son were decreased to various extent (60%, 65% and 31%, 40%, respectively). A c.911G>A heterozygous mutation (Gly276Glu) was detected in exon 6 of the proband, for which her father and son were heterozygotes. The same mutation was not found in her mother, brother and husband. Conservation analysis showed that the Gly276 is highly conserved across various species. By bioinformatic analysis, the PROVEAN (scored -6.214) indicated Gly276Glu was harmful, and MutationTaster (scored 0.976) suggested that it is pathogenic. Model analysis suggested there are two hydrogen bonds between Gly276 and Ile298 in the wild type protein. When Gly276 was replaced by Glu276, the original hydrogen bond did not change, but the side chain of Glu was extended, which added steric hindrance with the surrounding amino acids, which resulted in decreased protein stability.

CONCLUSIONThe heterozygous c.911G>A (Gly276Glu) mutation of the F5 gene probably underlies the decreased level of FⅤin the proband.

Adult ; Computational Biology ; Factor V ; chemistry ; genetics ; Factor V Deficiency ; genetics ; Female ; Humans ; Male ; Middle Aged ; Mutation ; Pedigree ; Phenotype

Hemorrhagic disease of newborn by combined blood clotting factor deficiencies is very rare. Combined deficiency of factor V and factor VIII is the most common form among these cases, and inherited by autosomal recessive trait. Clinical findings are easy bruising, post-traumatic bleeding and bleeding after tooth extractions, and the main laboratory findings are prolonged partial thromboplastin time (PTT) and prothrombin time (PT) that are different from hemophilia A only with prolonged PTT. We experienced a case of combined congenital deficiency of factor V and factor VIII in a 1-day-old boy. We report the case with brief review of literature.
Blood Coagulation ; Factor V Deficiency ; Factor V* ; Factor VIII* ; Hemophilia A ; Hemorrhage ; Humans ; Male ; Partial Thromboplastin Time ; Prothrombin Time ; Tooth Extraction ; Vitamin K Deficiency Bleeding