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Despite the exhaustive screening of F7 gene exons and exon-intron boundaries and promoter region, a significant proportion of mutated alleles remains unidentified in patients with coagulation factor VII deficiency. Here, we applied next-generation sequencing to 13 FVII-deficient patients displaying genotype-phenotype discrepancies upon conventional sequencing, and identified six rare intronic variants. Computational analysis predicted splicing effects for three of them, which would strengthen (c.571+78G>A; c.806-329G>A) or create (c.572-392C>G) intronic 5' splice sites (5'ss). In F7 minigene assays, the c.806-329G>A was ineffective while the c.571+78G>A change led to usage of the +79 cryptic 5'ss with only trace levels of correct transcripts (3% of wild-type), in accordance with factor VII activity levels in homozygotes (1-3% of normal). The c.572-392C>G change led to pseudo-exonization and frame-shift, but also substantial levels of correct transcripts (approx. 70%). However, this variant was associated with the common F7 polymorphic haplotype, predicted to further decrease factor VII levels; this provided some kind of explanation for the 10% factor VII levels in the homozygous patient. Intriguingly, the effect of the c.571+78G>A and c.572-392C>G changes, and particularly of the former (the most severe and well-represented in our cohort), was counteracted by antisense U7snRNA variants targeting the intronic 5'ss, thus demonstrating their pathogenic role. In conclusion, the combination of next-generation sequencing of the entire F7 gene with the minigene expression studies elucidated the molecular bases of factor VII deficiency in 10 of 13 patients, thus improving diagnosis and genetic counseling. It also provided a potential therapeutic approach based on antisense molecules that has been successfully exploited in other disorders., (Copyright© 2020 Ferrata Storti Foundation.)

While the immune response to hemophilic factors in hemophilia has been widely studied, little is known about the development of anti-Factor VII (FVII) antibodies in FVII deficiency. We developed a robust technique based on the x-MAP technology to detect the presence of antibodies against FVII and characterize their isotype and validated this method using blood samples from 100 patients with FVII deficiency (median FVII clotting activity [FVII:C]: 6%) and 95 healthy controls. Anti-FVII antibodies were detected in patients but also in some controls, although the concentration of total immunoglobulin G (IgGt) and IgG1 and IgG4 subclasses was significantly different between groups. The IgG1 subclass concentrations remained significantly different also when only untreated patients were compared with controls. This difference could partially be related to the F7 genotype, particularly in patients harboring the p.Arg139Gln mutation. This x-MAP-based method might be useful for assessing the immunogenicity of novel FVII compounds and of activated FVII (FVIIa) concentrates. Further prospective studies are needed to better understand the clinical relevance of these antibodies in the management of patients with FVII deficiency., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Because of the very short half-life of factor VII, prophylaxis in factor VII deficiency is considered a difficult endeavor. The clinical efficacy and safety of prophylactic regimens, and indications for their use, were evaluated in factor VII-deficient patients in the Seven Treatment Evaluation Registry. Prophylaxis data (38 courses) were analyzed from 34 patients with severe factor VII deficiency (<1-45 years of age, 21 female). Severest phenotypes (central nervous system, gastrointestinal, joint bleeding episodes) were highly prevalent. Twenty-one patients received recombinant activated factor VII (24 courses), four received plasma-derived factor VII, and ten received fresh frozen plasma. Prophylactic schedules clustered into "frequent" courses (three times weekly, n=23) and "infrequent" courses (≤ 2 times weekly, n=15). Excluding courses for menorrhagia, "frequent" and "infrequent" courses produced 18/23 (78%) and 5/12 (41%) "excellent" outcomes, respectively; relative risk, 1.88; 95% confidence interval, 0.93-3.79; P=0.079. Long term prophylaxis lasted from 1 to >10 years. No thrombosis or new inhibitors occurred. In conclusion, a subset of patients with factor VII deficiency needed prophylaxis because of severe bleeding. Recombinant activated factor VII schedules based on "frequent" administrations (three times weekly) and a 90 μg/kg total weekly dose were effective. These data provide a rationale for long-term, safe prophylaxis in factor VII deficiency.

Over 30 thromboembolic events have been reported in factor VII (FVII) deficiency either associated with previously asymptomatic forms or bleeding diathesis. Whether this coexistence is fortuitous or not is still a mater of debate. Nevertheless, it is well admitted that (i) thrombotic events occurring in FVII-deficient patients with any apparent triggering factors are very rare, (ii) surgical procedures, replacement therapy (especially containing activated factors) but also the presence of an antiphospholipid syndrome are frequently associated with these particular thrombotic events, (iii) in the same way, R304Q and A294V FVII variants appear to be more prevalent than other FVII equally frequent mutations and finally (iv) low FVII coagulant activity levels do not protect against thrombosis. Therefore, peri-operative thrombotic prophylaxis should be relevant for these particular FVII-deficient patients. However, safety, treatment modalities and specific indications of such an antithrombotic prophylaxis remain to be established., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Hereditary factor VII (FVII) deficiency is a rare autosomal recessive disorder. Deleterious mutations that prevent the synthesis of any amount of functional FVII have been associated with life-threatening haemorrhage in neonates. Here we report two infants, of Maghrebian origin, who suffered a fatal spontaneous cerebral haemorrhage. Investigation of the molecular basis for their severe FVII deficiency revealed novel mutations in a homozygous state within the F7 gene promoter: a single nucleotide substitution (c.-65G>C) and a 2bp deletion (c.-60&#95;-59delTT). To determine whether these promoter variants were responsible for the FVII deficiency, computer-assisted sequence analyses were performed. The data predicted a disrupted binding of both HNF4 and COUP-TF transcription factors with each variant. Concordantly, experimental results revealed an altered HNF4-induced transactivation in the promoter mutated variants. The execution of functional tests is critical to ensuring a complete understanding of the effect of any promoter mutant on FVII deficiency. Only then can an accurate molecular diagnosis be made and further genetic counselling and prenatal diagnosis be offered.

We report 2 asymptomatic homozygotes for the nonsense p.R462X mutation affecting the carboxy-terminus of coagulation factor VII (FVII, 466 aminoacids). FVII levels of 3-5% and 2.7 ± 0.4% were found in prothrombin time-based and activated factor X (FXa) generation assays with human thromboplastins. Noticeably, FVII antigen levels were barely detectable (0.7 ± 0.2%) which suggested a gain-of-function effect. This effect was more pronounced with bovine thromboplastin (4.8 ± 0.9%) and disappeared with rabbit thromboplastin (0.7 ± 0.2%). This suggests that the mutation influences tissue factor/FVII interactions. Whereas the recombinant rFVII-462X variant confirmed an increase in specific activity (~400%), a panel of nonsense (p.P466X, p.F465X, p.P464X, p.A463X) and missense (p.R462A, p.R462Q, p.R462W) mutations of the FVII carboxy-terminus resulted in reduced secretion but normal specific activity. These data provide evidence for counteracting pleiotropic effects of the p.R462X mutation, which explains the asymptomatic FVII deficiency, and contributes to our understanding of the role of the highly variable carboxy-terminus of coagulation serine proteases.

Inherited factor VII (FVII) deficiency is a rare autosomal recessive bleeding disorder mostly caused by point mutations. Large genomic re-arrangements at F7 locus could account for a fraction of mutant alleles that remain unidentified after DNA sequencing, because they escape conventional polymerase chain reaction (PCR)-based techniques. We report the first systematic screening of F7 for large re-arrangements, by semi-quantitative multiplex PCR of fluorescent fragments targeting the 9 exons and the promoter region. A well-characterised cohort of 43 unrelated patients either apparently homozygous for a F7 point mutation or carrying at least one unidentified F7 mutant allele participated in this study. Two large F7 re-arrangements were identified in two FVII-deficient pedigrees, including a discontinuous deletion involving two distinct portions of F7 whose proximal and distal end junctions were characterised. A simple and efficient method for the routine detection of gross alterations of F7, which accounted for 2.3% of mutant alleles in our sample, is now available in inherited FVII deficiency. This test should complement conventional PCR-based techniques not only in unsolved cases, but also where inheritance pattern analysis is not achievable.

Due to the wide molecular and clinical heterogeneities of inherited factor VII (FVII) deficiency, consensus guidelines for management of this coagulation disorder are not currently well established. Therefore, potential clinical, plasmatic or genetic criteria, that could be predictive for bleeding tendency in this condition, have been evaluated. Genotypic criteria including FVII genotypes and thrombophilic mutations are of particular interest to better understand some of the variations observed in bleeding phenotypes but they are still poorly informative for the management of surgery in FVII-deficient patients. Up to now, no plasma parameters have been found to be reliable predictors of bleeding risk. Nevertheless, tissue factor and platelet pathways remain to be explored. Finally, clinical history appears to be the best predictor of bleeding risk after haemostatic challenges in inherited FVII deficiencies. Furthermore, the absence of history of bleeding or mild bleeding phenotypes including menorrhagia, bruises and epistaxis (not inducing iron deficiency anaemia or requiring blood substitutive treatment) could enable minor surgery to be performed in FVII-deficient patients without blood replacement therapy.

Background and Objectives: Inherited factor VII (FVII) deficiency is a rare bleeding disorder characterized by a poor relationship between reported FVII clotting activity (FVII:C) and bleeding tendency. Our study was aimed at defining biological parameters that are possibly predictive for bleeding risk in this condition., Design and Methods: Forty-two FVII-deficient patients (FVII:C <30%) were classified into two opposite clinical groups defined as severe and non-or-mild bleeders. For each patient, plasma samples were collected and then investigated for FVII:C (using a sensitive method and human recombinant thromboplastin as the reagent), FVII antigen, activated FVII coagulant activity (FVIIa:C) and the free-form of tissue factor pathway inhibitor., Results: None of these tests could be used as highly accurate predictors of bleeding. Nevertheless, both FVII:C and FVIIa:C differed significantly between the two clinical groups. Using ROC-curve analysis, two critical values of 8% and 3mIU/mL for FVII:C and FVIIa:C, respectively, could be proposed to discriminate between severe bleeders and non-or-mild bleeders., Interpretation and Conclusions: A highly accurate diagnostic test for predicting bleeding tendency in inherited FVII deficiency still eludes definition, highlighting the fact that factors other than FVII itself interfere with the expression of bleeding phenotypes in this condition. Nevertheless, potential critical values using sensitive FVII:C and FVIIa:C methods may be useful in clinical laboratories for FVII-deficient patients. Those patients with FVII:C levels higher than 8% FVII:C or FVIIa:C higher than 3 mIU/mL, with no other hemostatic defect, seem to have a minimal risk of severe bleeding. Extended clinical studies are needed to support these findings.

Factor VII (FVII) is a plasma glycoprotein that plays a key role in the initiation of blood coagulation cascade. Inherited FVII deficiency is a rare autosomal recessive disorder with a wide heterogeneous clinical pattern. The severe form may be associated with intracranial haemorrhages occurring closely to birth with a high mortality rate. In the present article, we report two novel cases of neonatal intracerebral bleeding associated with FVII activity levels below 1% of normal. FVII genotyping investigations revealed particular genotypes including the deleterious Cys135Arg mutation and a novel Ser52Stop nonsense mutation at the homozygous state. Both mutations, through different mechanisms, are expected to be inconsistent with the production of functional FVII. These putative mechanisms are discussed through a review of the literature on phenotypic and genotypic characteristics of cerebral haemorrhages in severe inherited FVII deficiency.

Activated factor VII (FVIIa)/tissue factor enzyme complex is the initiator of the coagulation cascade in vivo. FVIIa is of particular interest because it has been found to induce haemostasis in various bleeding disorders. In order to evaluate the FVII threshold that is required to initiate the clotting cascade, we measured thrombin generation in FVII-depleted plasmas spiked with increasing amounts of normal pooled plasma and in inherited FVII-deficient plasmas. According to the literature, only trace amounts of FVII are sufficient to initiate blood coagulation in vitro. By contrast, results on inherited FVII-deficient plasmas showed a wide variety of the amounts of thrombin generated in plasmas with the same FVII coagulant activity levels. This suggests that the threshold of FVII required to initiate haemostasis in vivo depends on one or more, hitherto unknown, plasmatic or cellular factors., (Copyright 2003 S. Karger AG, Basel)

Inherited factor VII (FVII) deficiency is a rare autosomal disorder characterized by a weak relationship between FVII activity (FVII:C) and operative bleeding risk. We report a retrospective study of 17 patients with a FVII:C below 0.1 IU/ml, in whom surgery was performed without any replacement therapy. Clinical and biological data were analysed to establish predictive criteria for bleeding tendency. We found that systematic preoperative replacement therapy may not be necessary for 'minor' surgical procedures, for patients suffering from inherited FVII deficiency, unless the clinical history includes severe haemorrhagic symptoms such as haemarthrosis, severe haematomas (even of soft tissue) or abundant epistaxis.

Hereditary blood coagulation factor VII (FVII) deficiency is a rare autosomal recessive bleeding disorder resulting from variants in the gene encoding FVII (F7). Integration of genetic variation with functional consequences on protein function is essential for the interpretation of the pathogenicity of novel variants. Here, we describe the integration of previous locus‐specific databases for F7 into a single curated database with enhanced features. The database provides access to in silico analyses that may be useful in the prediction of variant pathogenicity as well as cross‐species sequence alignments, structural information, and functional and clinical severity described for each variant, where appropriate. The variant data is shared with the F7 Leiden Open Variation Database. The updated database now includes 221 unique variants, representing gene variants identified in 728 individuals. Single nucleotide variants are the most common type (88%) with missense representing 74% of these variants. A number of variants are found with relatively high minor allele frequencies that are not pathogenic but contribute significantly to the likely pathogenicity of coinherited variants due to their effect on FVII plasma levels. This comprehensive collection of curated information significantly aids the assessment of pathogenicity. [ABSTRACT FROM AUTHOR]

Emphasizes the reliability of detection assay and linkage analysis in the diagnosis of severe inherited blood coagulation factor VII (FVII) deficiency. Information on the case of a two-year-old girl with FVII; Overview of prenatal mutation screening; Description of mutation-specific detection assays.