Novel factor VII gene mutations in six families with hereditary coagulation factor VII deficiency.

INTRODUCTION: Hereditary human coagulation factor VII (FVII) deficiency is an inherited autosomal recessive hemorrhagic disease involving mutations in the F7 gene. The sites and types of F7 mutations may influence the coagulation activities of plasma FVII (FVII: C) and severity of hemorrhage symptoms. However, the specific mutations that impact FVII activity are not completely known. METHODS: We tested the coagulation functions and plasma activities of FVII in seven patients recruited from six families with hereditary FVII deficiency and sequenced the F7 gene of the patients and their families. Then, we analyzed the genetic information from the six families and predicted the structures of the mutated proteins. RESULTS: In this study, we detected 11 F7 mutations, including four novel mutations, in which the mutations p.Phe84Ser and p.Gly156Cys encoded the Gla and EGF domains of FVII, respectively, while the mutation p.Ser339Leu encoded the recognition site of the enzymatic protein and maintained the conformation of the catalytic domain structure. Meanwhile, the mutation in the 5' untranslated region (UTR) was closely associated with the mRNA regulatory sequence. CONCLUSION: We have identified novel genetic mutations and performed pedigree analysis that shed light on the pathogenesis of hereditary human coagulation FVII deficiency and may contribute to the development of treatments for this disease.

Compound Heterozygous Mutations in the F7 Gene in 2 Unrelated Families With Congenital Factor VII Deficiency.

Factor VII (FVII) deficiency is a rare bleeding disorder normally caused by homozygous and compound heterozygous mutations in the F7 gene. Whole-exome sequencing was performed to identify F7 mutations in 3 individuals from 2 unrelated families who were diagnosed with FVII deficiency. Four compound heterozygous mutations were identified and validated in these 3 probands with FVII deficiency. Among the 4 identified mutations, NM_000131.4:c.572-1_581del, NM_000131.4:c.1250A>G (p.Tyr417Cys), and NM_000131.4:c.647G>T (p.Gly216Val) were novel. All 3 novel mutations were predicted to be likely pathogenic by the American College of Medical Genetics and Genomics/Association for Molecular Pathology guidelines.

Successful Splenectomy Management in a Patient With Moderate Factor VII Deficiency and Concomitant Severe Hereditary Spherocytosis.

By the advent of the effective therapies for many coagulation diseases and hereditary spherocytosis (HS), patient's survival has been improved significantly; however, if patients are diagnosed late or left untreated, both diseases could ominously be life threatening. Concurrent occurring of factor VII (FVII) deficiency and HS is extremely rare and there is no literature report that explain this condition, thus far. In this study, we confronted a 9-year-old female patient diagnosed with HS and enlarged spleen as a result of this blood disorder. Given to her sever signs and symptoms of splenomegaly, she was candidate for emergent splenectomy. However, assessment of coagulation tests revealed a prolonged prothrombin time, suggesting the moderate FVII deficiency. With a multidisciplinary consultation, we decided to performed total splenectomy with prophylaxis administration of totally 6 doses of active recombinant FVII, initiated 1 hour before surgery and followed until 30 hours postoperation. As a result of cautious undertaken in Mofid Children's Hospital, the patient did not experience any hemostatic defect. Patient is now 14-year-old, generally well-being under regular surveillance of FVII deficiency.

Novel IVS7+1G>T mutation of life-threatening congenital factor VII deficiency in neonates: A retrospective study in China.

In neonates, congenital factor VII deficiency (FVIID) is characterized by central nervous system bleeding and gastrointestinal hemorrhage, often resulting in poor prognosis and high mortality.To improve understanding of FVIID in neonates in Asia, we retrospectively analyzed the clinical manifestations, diagnosis, treatment, clinical course, and genetic diagnosis of 2 cases of neonatal FVIID in the Department of Neonatology, Guangzhou Women and Children's Medical Center, Guangzhou, China, from January 2007 to December 2017 and performed a review of the relevant literature.Both neonates were female and presented with severe gastrointestinal tract and intracranial hemorrhage. The laboratory findings were characterized by repeated and non-vitamin K1-dependent prolonged of the prothrombin time (PT), Factor VII (FVII) activity was 1.5% and 3%, respectively. Both neonates died of severe intracranial hemorrhage, at 31 days and 6 months after birth, respectively. Gene sequencing results revealed a homozygous mutation in the FVII gene splice site (IVS7+1G>T) in both cases. Upon review of relevant literature published since 1996, we identified 19 cases of neonatal FVIID. The patients were full-term neonates with onset of symptoms mostly within 7 days after birth (73.7%), which included gastrointestinal bleeding (blood stool, vomiting blood; 31.6%), nervous system signs (drowsiness, convulsions, poor response; 26.3%), severe intracranial hemorrhage (84.2%), significantly prolonged PT with significantly decreased FVII activity (89.5%), high mortality, and disability (68.4%). Gene sequencing was performed in 9 of the 19 children evaluated and revealed a mutation in the FVII gene in all cases.FVIID can be clinically diagnosed based on the presence of prolonged PT that is difficult to correct and significantly decreased FVII activity (≤5%). As mutations in some sites are associated with severe bleeding, genetic diagnosis represents a useful tool for prenatal diagnosis of FVIID. In brief, we should pay great attention to the FVIID onset of the neonatal period, although it is rare but result in life-threatening bleeding with poor prognosis.

An overview of inherited factor VII deficiency.

Factor VII (FVII) deficiency is the most common of the Rare Inherited Coagulation Disorders. The inheritance is autosomal recessive but there is variable penetrance. Overall there is poor correlation between the FVII level and the bleeding phenotype. Heterozygotes may have significant bleeding and severe homozygotes, or compound heterozygotes can be asymptomatic. Typically, homozygotes have FVII levels <10% and heterozygotes have levels above that. In most cases bleeding is uncommon with FVII levels>10-20%. A personal and family history is essential to determine the bleeding risk and to plan for surgical and obstetrical prophylaxis. Severe bleeding complications including central nervous system bleeding, gastrointestinal system bleeding and bleeding into the joints occurs in 10-15% of FVII deficient patients. Mucocutaneous bleeding is a common symptom but 30% of patients are asymptomatic. Fifty to 69% of women have heavy menstrual bleeding. Due to the limited number of publications regarding this rare disorder there are no consensus guidelines. There is registry data which has led to the best recommendations for treatment of bleeding episodes, initiation of long-term prophylaxis in addition to surgical plus ante and peripartum prophylaxis. Recombinant FVII concentrate is the best replacement therapy and a review of treatment and prophylaxis dosing is discussed.

Hemophagocytic lymphohistiocytosis and congenital factor VII deficiency: a case report.

BACKGROUND: Hemophagocytic lymfohistiocytosis (HLH) is a rare, life-threatening hyperinflammation, characterized by immune system over-activation resulting in hemophagocytosis. HLH could appear as a primary disease caused by mutations of immune-regulatory genes, or develop as a result of viral or bacterial infections, or malignancy. Congenital factor VII (FVII) deficiency is a rare autosomal recessive disorder characterized by prolonged prothrombin time (PT) and low FVII, which may increase bleeding risk. CASE PRESENTATION: A 50-year-old woman was admitted for a fever persisted for 20 days, presenting with cytopenia, high hyperferritinemia, low activity of NK cells. Bone marrow aspiration showed hemophagocytosis. CT scanning found pulmonary infection. EBV and CMV were not detected. Genetic scanning did not find pathogenic mutation of a HLH NGS panel including 26 genes. This patient was treated as recommended by the HLH 2004 Guidelines. Coagulation tests identified FVII deficiency. Genetic analysis of F7 gene in the patient and her family members identified recurrent compound heterozygous F7 c.64 + 5G > A and c.1224 T > G (p.His408Gln) mutations in this patient and her brother who showed postoperative hemorrhage after surgical resection of renal cell carcinoma. Heterozygotes in this family were asymptomatic. CONCLUSIONS: To our knowledge, this is the first report of HLH in combination with congenital FVII deficiency in Chinese population.

Heterozygous congenital Factor VII deficiency with the 9729del4 mutation, associated with severe spontaneous intracranial bleeding in an adolescent male.

BACKGROUND: In congenital Factor (F) VII deficiency bleeding phenotype and intrinsic FVII activity levels don't always correlate. Patients with FVII activity levels <30% appear to have a higher bleeding propensity, but bleeding can also occur at higher FVII activity levels. Reasons for bleeding at higher FVII activity levels are unknown, and it remains challenging to manage such patients clinically. CASE: A 19year old male with spontaneous intracranial hemorrhage and FVII activity levels of 44%, requiring emergent surgical intervention and a strategy for FVII replacement. Genotyping showed the rare heterozygous FVII 9729del4 mutation. Bleed evacuation was complicated by epidural abscess requiring craniectomy, bone graft procedures, and prolonged administration of recombinant human (rh) activated FVII (FVIIa). The patient recovered without neurological deficits, and remains on prophylactic low dose treatment with rhFVIIa in relation to risky athletic activities. CONCLUSION: For clinicians, it is important to recognize that effects of rhFVIIa within these pathways are independent of its contribution to blood clot formation and cannot be assessed by clotting assays. Reduced FVII levels should therefore not be dismissed, as even a mild reduction may result in spontaneous bleeding. Treatment of mild FVII deficiency requires a careful case-by-case approach, based on the clinical scenario.

Cryptic 13q34 and 4q35.2 Deletions in an Italian Family.

Variations of DNA sequences in the human genome range from large, microscopically visible chromosome anomalies to single nucleotide changes. Submicroscopic genomic copy number variations, i.e. chromosomal imbalances which are undetectable by conventional cytogenetic analysis, play an intriguing clinical role. In this study, we describe the clinical consequences of the concurrent presence of an interstitial deletion in 13q34 and a terminal deletion in 4q35.2 in an Italian family. The index patient, a 19-year-old male, as well as his 12-year-old sister are carriers of both deletions, one of maternal and the other of paternal origin. The phenotype includes language delay, multiorgan involvement and bleeding diathesis with mild deficiency of factors X and VII. In the sister, the concomitant presence of Noonan syndrome may partly explain the clinical symptoms. The deleted region on chromosome 13 involves several genes (ATP11A, MCF2L, F7, F10, PROZ, PCID2, CUL4A, and LAMP1); some of these seem to play a role in the proband's phenotype. The terminal deletion in 4q35.2 contains other OMIM genes (FRG1, FRG2 and DBET); moreover, the 4q region is reported as a susceptibility locus for Crohn's disease, diagnosed in the proband's father. To our knowledge, this is the first report of a family with these 2 submicroscopic copy number changes. We tried to relate the clinical phenotype of the proband and his family to the molecular function of the involved genes.

Factor VII Tokushima: the first case of factor VII Cys22Gly with the development of myocardial infarction in the proband receiving recombinant factor VIIa replacement therapy.

An 81-year-old man was referred to our department because of suspected factor VII (FVII) deficiency. His FVII activity was under 1%, whereas the FVII activity levels of his son and granddaughter were 65 and 109%, respectively. The nucleotide at position 3886 of his FVII gene was homozygous for G. A single T to G substitution results in the replacement of wild-type Cys at residue 22 by Gly. His son was heterozygous for G and T at position 3886, whereas his granddaughter was homozygous for wild-type T. These results suggest that he was homozygous for FVII Cys22Gly. He underwent radiofrequency ablation (RFA) for hepatocellular carcinoma, receiving 20 µg/kg of recombinant FVIIa prior to RFA and 10 µg/kg of recombinant FVIIa twice after RFA. He showed no bleeding tendency; however, a myocardial infarction was diagnosed and percutaneous coronary intervention was performed.

Genotype and phenotype relationships in 10 Pakistani unrelated patients with inherited factor VII deficiency.

Inherited factor VII (FVII) deficiency is one of the commonest rare bleeding disorders. It is characterized by a wide molecular and clinical heterogeneity and an autosomal recessive pattern of inheritance. Factor VII-deficient patients are still scarcely explored in Pakistan although rare bleeding disorders became quite common as a result of traditional consanguineous marriages. The aim of the study was to give a first insight of F7 gene mutations in Pakistani population. Ten unrelated FVII-deficient patients living in Pakistan were investigated (median FVII:C = 2%; range = 2-37%). A clinical questionnaire was filled out for each patient and direct sequencing was performed on the coding regions, intron/exon boundaries and 5' and 3' untranslated regions of the F7 gene. Nine different mutations (eight missense mutations and one located within the F7 promoter) were identified on the F7 gene. Five of them were novel (p.Cys82Tyr, p.Cys322Ser, p.Leu357Phe, p.Thr410Ala, c-57C>T, the last being predicted to alter the binding site of transcription factor HNF-4). Half of the patients had single mutations in Cys residues involved in disulfide bridges. The p.Cys82Arg mutation was the most frequent in our series. Six of seven patients with FVII:C levels below 10% were homozygous in connection with the high percentage of consanguinity in our series. In addition, we graded the 10 patients according to three previously published classifications for rare bleeding disorders. The use of the bleeding score proposed by Tosetto and co-workers in 2006 appears to well qualify the bleeding tendency in our series.

Factor VII deficiency: a single-center experience.

Congenital factor VII deficiency is the most common form of rare coagulation factor deficiencies. This article presents a retrospective evaluation of 73 factor VII deficiency cases that had been followed at our center. The study consisted of 48 males and 25 females (2 months-19 years). Thirty-one (42.5%) of them were asymptomatic. Out of symptomatic patients, 17 had severe clinical symptoms, whereas 8 presented with moderate and 17 with mild symptoms. The symptoms listed in order of frequency were as follows: epistaxis, petechia or ecchymose, easy bruising, and oral cavity bleeding. The genotype was determined in 8 patients. Recombinant activated factor VII (rFVIIa) was used to treat 49 bleeding episodes in 8 patients after 2002. In 2 patients with repeated central nervous system bleeding prophylaxis with rFVIIa was administered. No allergic and thrombotic events were observed during both treatment and prophylaxis courses. Antibody occurrence was not detected in the patients during treatment.

A novel missense mutation close to the charge-stabilizing system in a patient with congenital factor VII deficiency.

Congenital factor VII (FVII) deficiency is a rare autosomal recessive bleeding disorder. Its clinical manifestation and mutational spectrum are highly variable. The purpose of this study was to identify and characterize the mutation causing the FVII deficiency in a Chinese patient and his family. The FVII gene was analyzed by genomic DNA sequencing, and the FVII levels in patient's plasma were measured with an enzyme-linked immunoabsorbent assay (ELISA) and one-stage prothrombin time based method. In addition, the FVII-Phe190 mutant identified in the pedigree was expressed in the HEK293 cells, and the subcellular localization experiments in the Chinese hamster ovary (CHO) cells were performed. The patient had a prolonged prothrombin time and low levels of both FVII antigen and activity, and two heterozygous mutations were identified in F7 gene (NG-009262.1): a g.15975 G>A in the splice receptor site of intron 6 and a novel g.16750 C>T in exon 8 resulting in Ser190 to Phe190 replacement. In expression experiments, the reduced antigen and activity levels of FVII-Phe190 in the culture medium were found, whereas an ELISA and Western blotting analysis of FVII revealed that mutant FVII-Phe190 was synthesized in the cells as the wild-type FVII-Ser190. And FVII-Phe190 was found in endoplasmic reticulum and Golgi apparatus. Compound heterozygous mutations in F7 gene should be responsible for the FVII deficiency in this patient. The FVII-Phe190 can normally be synthesized and transported from endoplasmic reticulum to Golgi apparatus, but degraded or inefficiently secreted.

Imaging and intervention of paraneoplastic effect of a right atrial myxoma on factor VII activity levels.

We present the case of a 64-year-old Pakistani man with right atrial myxoma, recently diagnosed with acquired severe factor VII (FVII) deficiency. The patient presented with a history of chronic hiccups and weight loss. Initial evaluation revealed an isolated prolonged prothrombin time, severely reduced FVII activity level, and a giant right atrial myxoma protruding into the right ventricle on computed tomographic thorax and echocardiography. After surgical resection, the patient maintained normal prothrombin time with increased FVII activity level in the immediate 24 hours postoperatively, and a dramatically high level of FVII activity at the 2-month follow-up. We believe that the paraneoplastic effect of myxoma on the FVII activity levels is previously unreported. In addition, we believe that hiccups as a presenting symptom for a myxoma with an atypical origin from the lateral wall of the right atrium has not been reported.

Severe deficiency of coagulation Factor VII results in spontaneous cardiac fibrosis in mice.

Mice genetically modified to produce low levels (approximately 1% of wild-type) of coagulation FVII presented with echocardiographic evidence of heart abnormalities. Decreases in ventricular size and reductions in systolic and diastolic functions were found, suggestive of a restrictive cardiomyopathy and consistent with an infiltrative myopathic process. Microscopic analysis of mouse hearts showed severe patchy fibrosis in the low-FVII mice. Haemosiderin deposition was discovered in hearts of these mice, along with increases in inflammatory cell number, ultimately resulting in widespread collagen deposition. Significant increases in mRNA levels of TGFbeta, TNFalpha and several matrix metalloproteinases in low-FVII mice, beginning at early ages, supported a state of cardiac remodelling associated with the fibrotic pathology. Mechanistic time-course studies suggested that cardiac fibrosis in low-FVII mice originated from bleeding in heart tissue, resulting in the recruitment of leukocytes, which released inflammatory mediators and induced collagen synthesis and secretion. These events led to necrosis of cardiomyocytes and collagen deposition, characteristics of cardiac fibrosis. The results of this study demonstrated that haemorrhagic and inflammatory responses to a severe FVII deficiency resulted in the development of cardiac fibrosis, observed echocardiographically as a restrictive cardiomyopathy, with compromised ventricular diastolic and systolic functions.

Hereditary factor VII deficiency in the Alaskan Klee Kai dog.

BACKGROUND: Hereditary factor VII (FVII) deficiency is characterized as a mild bleeding disorder in Beagles, caused by a missense mutation in exon 5 of the FVII gene. An Alaskan Klee Kai dog with severe bleeding after trauma was diagnosed with FVII deficiency based on coagulation testing. Molecular analyses were undertaken to identify the genetic basis of the defect in this breed. HYPOTHESIS: FVII deficiency in Alaskan Klee Kai dogs is caused by a mutation in the FVII gene. ANIMALS: Eighteen client-owned Alaskan Klee Kai. METHODS: Coagulation screening tests and factor assays were performed to characterize the coagulopathy. All coding regions of the propositus' FVII gene were sequenced. Amplification of exon 5, sequencing, and Mnl I restriction digest experiments were performed to screen for a point mutation in the remaining 17 dogs. RESULTS: FVII deficiency was diagnosed in 6 dogs with a median FVII activity (FVII: C) of 5% (reference range, 50 150%). All FVII-deficient Alaskan Klee Kai were homozygous for the same mutation as FVII-deficient Beagles (ie, a G to A transition), resulting in substitution of glycine 96 by glutamic acid. An overlap in the FVII: C values obtained from heterozygote and wild-type dogs precluded accurate detection of carriers without genetic screening. CONCLUSIONS AND CLINICAL IMPORTANCE: FVII deficiency may be associated with a bleeding tendency and should be considered in Alaskan Klee Kai dogs with prolonged prothrombin times. Plasma FVII: C accurately identifies affected dogs, but deoxyribonucleic acid testing is required for identification of carriers.

Intracellular evaluation of ER targeting elucidates a mild form of inherited coagulation deficiency.

Missense mutations reduce protein levels through several molecular mechanisms. Among them, altered targeting to endoplasmic reticulum (ER) and its relationship with clinical phenotypes in patients have been poorly investigated. To address this point, we studied the prepeptide mutations (L-48P, L-42P) associated with mild deficiency of factor VII (FVII), the serine-protease triggering blood coagulation. Mutations were introduced into the native FVII to evaluate secreted and intracellular protein levels, and into a chimeric FVII-GFP to study ER targeting in living cells. In conditioned medium from stably or transiently transfected cells, expression levels of the -48PFVII (9% and 55%, respectively) and particularly those of the -42PFVII (2% and 12%) were decreased compared with those of WtFVII, indicating the causative nature of mutations. Markedly reduced protein levels were observed in cell organelles for -48PFVII (10.5 +/- 4.9 ng/mL; Wt-FVII, 130 +/- 43.4 ng/mL) and -42PFVII (approximately 5 ng/mL), thus suggesting impaired ER targeting. Fluorescence of the -48PFVII-GFP and -42PFVII-GFP was diffuse, covered the nucleus, and declined upon plasma membrane permeabilization with digitonin, which demonstrated mislocalization of variants in the cytosol. Noticeably, the residual fluorescence of -48PFVII-GFP (10%) and -42PFVII-GFP (20%) in organelles was fairly compatible with FVII levels in patients' plasma. The studies with the native and chimeric proteins indicated that both prepeptide mutations were associated with residual expression of normal FVII, which explained the mild form of FVII deficiency in patients. This approach, extendable to other coagulation serine proteases, clearly contributed to elucidate the relationship of genotype with plasma and clinical phenotype.