OBJECTIVE: To summarize the clinical features and management of two brothers affected with X-linked inhibitor of apoptosis protein (XIAP) deficiency. METHODS: This study retrospectively analyzed the clinical presentations, treatment, and follow-up of two brothers with XIAP deficiency diagnosed at Shanghai Children's Hospital in 2020, and summarized similar cases recorded in databases such as PubMed, Wanfang, Chinese Medical Association Journals, and WIP from January 2006 to November 2024. This study was approved by the Medical Ethics Committee of our hospital (Ethics No.: 2025R128-E01). RESULTS: Patient 1 was the younger brother, who presented at 8 years of age with growth retardation, folliculitis, erythema nodosum, and perineal abscess. Sequencing revealed that he has carried a hemizygous c.566T>C (p.Leu189Pro) variant of the XIAP gene, which was inherited from his mother. He was allergic to infliximab treatment and underwent allogeneic stem cell transplantation (HSCT) in January 2021. During a follow-up of 3 years and 10 months post-transplantation, he showed no gastrointestinal symptoms and had a good outcome. Patient 2 was the elder brother, who presented at 10 years and 6 months of age with growth retardation, rash, and anal fistula. Genetic testing revealed the same variant. He was treated with oral azathioprine but did not have regular follow-ups. At 14-years-and-6-months of age, he had developed severe gastrointestinal infection and hemophagocytic lymphohistiocytosis, which was alleviated after treatment with antibiotics, glucocorticoids, immunoglobulin, and rituximab. He is currently being prepared for HSCT. A total of 13 publications were retrieved, which involved 64 patients from 23 families, with 23 different variants identified. The main clinical manifestations included splenomegaly (34 cases, 53.1%), hemophagocytic lymphohistiocytosis (27 cases, 42.2%), and inflammatory bowel disease or colitis (20 cases, 31.8%). There were significant phenotypic differences among patients from the same family. Thirteen patients (20.3%) underwent HSCT, with a survival rate of 61.5%. CONCLUSION For male children with early onset, poor treatment response, especially those with unexplained splenomegaly and IBD-like symptoms, early genetic testing is recommended. HSCT is a safe and effective treatment for XIAP deficiency. For patients with developmental delay, early onset, and severe IBD phenotype, early transplantation is recommended.
Humans ; Male ; X-Linked Inhibitor of Apoptosis Protein/deficiency* ; Child ; Genetic Diseases, X-Linked/therapy* ; Phenotype ; Siblings ; Retrospective Studies ; Hematopoietic Stem Cell Transplantation

OBJECTIVE: To explore the results of four types of Urea cycle disorders (UCDs) in newborns from the Xuzhou region, assess the efficacy of newborn screening by tandem mass spectrometry (MS/MS), and analyze their genetic characteristics. METHODS: A retrospective analysis was performed using tandem mass spectrometry to screen for inherited metabolic disorders in 691 712 newborns at the Maternal and Child Health Care Hospital of Xuzhou from November 2015 to December 2023. Ten children (cases 1-10) were diagnosed with Ornithine transcarbamylase deficiency (OTCD), Carbamoylphosphate synthase 1 deficiency (CPS1D), Arginase deficiency (ARGD), and Argininosuccinate synthase deficiency (ASSD) based on MS/MS and genetic testing. This study was approved by the Medical Ethics Committee of Xuzhou Maternity and Child Health Care Hospital (Ethics No.XZFY2024-051K-01J). RESULTS: A total of 691 712 neonates were screened for UCDs using MS/MS, which identified 1 237, 1 237, 510, and 1 009 initial positive cases for OTCD, CPS1D, ASSD, and ARGD, respectively. After genetic testing, 1 case of OTCD, 1 case of CPS1D, 1 case of ASSD, and 7 cases of ARGD were confirmed. The overall positive predictive value for these four UCDs was 0.362%. Among the 10 diagnosed UCD cases, four novel variants were identified, which included OTC: c.1024C>A (p.L342M) and ASS1: c.826A>G (p.M276V), c.695C>T (p.P232L) and c.694C>T (p.P232S). Bioinformatic analysis has rated these as variants of uncertain clinical significance or likely pathogenic based on guidelines from the American College of Medical Genetics and Genomics (ACMG). CONCLUSION The incidence of four UCDs in neonates from the Xuzhou area is relatively low, and there is a correlation between genetic variants and clinical phenotypes. For novel variants with uncertain clinical significance or suspected pathogenicity, their pathogenicity should be clarified in conjunction with clinical and biochemical indicators. The four novel pathogenic variants of UCDs identified in this study have enriched the mutational spectrum of UCDs-associated genes in the Xuzhou region.
Humans ; Infant, Newborn ; Tandem Mass Spectrometry/methods* ; Urea Cycle Disorders, Inborn/diagnosis* ; Neonatal Screening/methods* ; Genetic Testing/methods* ; Female ; Retrospective Studies ; Male ; Ornithine Carbamoyltransferase Deficiency Disease/diagnosis* ; Mutation ; Carbamoyl-Phosphate Synthase (Ammonia)/genetics* ; Ornithine Carbamoyltransferase/genetics*

OBJECTIVE: To analyze a Chinese pedigree with Hereditary coagulation factor Ⅻ (FⅫ) deficiency duo to variants of F12 gene and explore its molecular pathogenesis. METHODS: A patient who underwent laparoscopic cystectomy at the Department of Gynecology of the First Affiliated Hospital of Wenzhou Medical University in June 2012 was selected as the study subject. Coagulation factor indexes of the proband and her family members (5 individuals from three generations) were determined. All exons, flanking sequences, 5' and 3' untranslated regions of the F12 gene of the proband and her family members were analyzed by direct sequencing. Three bioinformatics software was used to analyze the conservation, pathogenicity and protein model of the variant. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No. 2012-17). RESULTS: The activated partial thromboplastin time (APTT), FⅫ activity (FⅫ:C) and FⅫ antigen (FⅫ:Ag) of the proband was 180.0 s, 1.0% and 2.1%, respectively. DNA sequencing revealed that she has harbored compound heterozygous variants of the F12 gene, namely c.712_713insT (p.Cys238Leufs *73) in exon 8 and c.1561G>A (p.Glu521Lys) in exon 13. Her mother and younger son were heterozygous for the p.Cys238Leufs*73 variant, while her older son was heterozygous for the p.Glu521Lys variant. Bioinformatic analysis suggested that Cys238 is highly conserved and p.Cys238Leufs*73 is a pathogenic variant, which eventually resulted in a truncated protein. CONCLUSION The c.712_713insT and c.1561G>A compound heterozygous variants of the F12 gene probably underlay the decreased FⅫ level in this pedigree, among which c.712_713insT (NM_000505) was unreported previously.
Adult ; Female ; Humans ; Male ; Middle Aged ; Base Sequence ; China ; Factor XII/genetics* ; Heterozygote ; Mutation ; Pedigree ; Factor XII Deficiency/genetics* ; East Asian People

OBJECTIVE: To elucidate the clinical and genetic characteristics of familial cases with Glucose transporter type 1 deficiency syndrome (Glut1DS). METHODS: A survey of family history was conducted on children (proband) with Glut1DS who had visited Peking University First Hospital between November 2008 and April 2024 by focusing on the clinical manifestations of family members. Peripheral venous blood (2 mL) was collected from the pediatric patients and their parents. Genomic DNA was extracted and sequenced subsequently. Sanger sequencing was performed to validate the identified variant sites of the SLC2A1 gene in the probands and their family members. The pathogenicity of suspected variants was analyzed according to the 2015 American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines for the Interpretation of Sequence Variants. The clinical features, auxiliary examinations, and mutational characteristics of family members with SLC2A1 variants were analyzed. This study has been approved by the Clinical Research Ethics Committee of Peking University First Hospital (Ethics No. 2021 Research 332). RESULTS: Among 87 cases with Glut1DS, 10 families with autosomal dominate inherited cases were identified, accounting for 11.0% of the cases. Of the 11 children, 8 were boys and 3 were girls. The onset of the disease had ranged from 3 months to 120 months (median 6 months), with 4 cases of early-onset classic type, 2 cases of late-onset classic type, and 5 cases of non-classic type. Six children had seizures, and 7 exhibited movement disorders. Seven children underwent developmental assessment, of which 3 had mild developmental delay, 2 were borderline, and 2 were normal. Nine children underwent lumbar puncture. The cerebrospinal fluid glucose levels ranged from 1.45 to 2.25 mmol/L (median 1.86 mmol/L), and the cerebrospinal fluid to blood glucose ratios ranged from 0.29 to 0.44 (median 0.35). Among the 8 fathers with SLC2A1 gene variants, 4 were asymptomatic, 2 developed paroxysmal exercise-induced movement disorders (PED) in childhood and adulthood, respectively. 1 had poor memory since childhood, 1 developed migraines during adolescence, and his sister was an asymptomatic carrier. The father with childhood-onset PED had a cerebrospinal fluid test with CSF glucose of 1.85 mmol/L. Of the 3 mothers with SLC2A1 gene mutations, 1 was an asymptomatic carrier; 2 developed PED in childhood and after the age of 20, respectively. The mother who developed PED in childhood also had psychomotor developmental delay. Genetic testing results revealed that among 10 families, 8 carried missense variants, 1 carried a nonsense variant, and 1 carried a small fragment insertion leading to a frameshift variant. Among the 11 cases, SLC2A1 gene variants in 8 children were inherited from their fathers, while in 3 cases, the variants were inherited from their mothers. The pathogenicity of the genetic variants was evaluated according to the Standards and Guidelines for the Interpretation of Sequence Variants published by the ACMG. Among the 8 variants identified in the 10 families, 4 were classified as pathogenic variants, 1 as likely pathogenic, and 3 as variants of uncertain significance (VUS). Four variant sites, including c.204_205insTCTC (p.V69fs), c.412G>C (p.G138R), c.431T>G (p.V144G), and c.875A>G (p.Y292C), were not previously reported in the literature. Among these, the latter three were categorized as VUS. CONCLUSION Familial Glut1DS account for 11.0% of the cases in China, with the majority of SLC2A1 gene variants inherited from the fathers, predominantly missense mutations, and with an autosomal dominant inheritance pattern. Probands tend to have earlier onset and more severe symptoms than their parents, who often present with mild or no symptoms.
Humans ; Male ; Female ; Glucose Transporter Type 1/deficiency* ; Monosaccharide Transport Proteins/deficiency* ; Child ; Child, Preschool ; Carbohydrate Metabolism, Inborn Errors/genetics* ; Mutation ; Infant ; Pedigree ; Adolescent ; Adult

The 1985 version of WHO G6PD variation classification is no longer suitable for the development of modern medicine, and it has been revised by the WHO G6PD Technical Advisory Group. According to the genetic variation classification of G6PD by WHO in 2024, G6PD deficiency is divided into four categories: Class A: enzyme activity < 20% with chronic hemolytic anemia; Class B: enzyme activity < 45% in association with acute hemolysis caused by inducement; Class C: enzyme activity > 60%, no hemolysis; Class U: for those with incomplete clinical phenotypic information, and will be classified again with new clinical evidence obtained. The clinical implications of the new classification include: (1) To guide the prevention and treatment of G6PD deficiency; (2) To better understand the pathological and non-pathological status of G6PD deficiency, which lays a foundation for re-determining the birth defect rate in China; (3) To guide the safe use of anti-malarial drugs and related oxidizing drugs in G6PD deficient patients; (4) To promote the hierarchical health management of G6PD deficient individuals throughout their life cycle; (5) To guide the pathogenicity rating of G6PD gene variation; (6) To unify the diagnostic criteria for global G6PD deficiency, promote the homogenization, comparability and data sharing of global relevant data, and lay the foundation for the application of artificial intelligence.
Humans ; Glucosephosphate Dehydrogenase Deficiency/diagnosis* ; Glucosephosphate Dehydrogenase/genetics* ; Genetic Variation ; World Health Organization ; China

OBJECTIVE: To explore the clinical characteristics and variant of FBP1 gene in a child with Fructose-1,6-bisphosphatase deficiency (FBP1D), and review the literature on the clinical characteristics and gene mutations of FBP1D in the Chinese population. METHODS: A FBP1D proband due to variant of FBP1 gene who was admitted to Women and Children's Hospital of Ningbo University on August 10, 2021 due to "vomiting for 1 day" was selected as the study subject. Clinical data of the child were retrospectively collected. Whole exome sequencing (WES) was performed on the child, and candidate variants identified in the child were validated by Sanger sequencing in both the child and his parents. The difference between wild type and variant FBP1 protein were compared using AlphaFold v3.0.1 and PyMOL v2.5.6. The pathogenicity of candidate variant was rated according to the Standards and Guidelines for the Interpretation of Sequence Variants released by American College of Medical Genetics and Genomics (ACMG) (hereinafter referred to as ACMG guidelines). Using keywords such as "FBP1 gene" and "fructose-1,6-bisphosphatase deficiency" both in Chinese and English, relevant literature on FBP1D patients caused by FBP1 gene variants in the Chinese population were retrieved from the PubMed database, CNKI, and Wanfang Data Knowledge Service Platform, and the genetic variant and clinical phenotypes of FBP1D patients reported in the literature were analyzed. The literature retrieval time was set from the establishment of each database to October 31st, 2024. This study was approved by the Women and Children's Hospital of Ningbo University (Ethics No.: 2020-048). RESULTS: The proband was presented with repeated infections, nausea, vomiting, and mental illness. The auxiliary examination revealed hypoglycemia, acidosis, liver and kidney dysfunction, hyperlipidemia and hepatomegaly. WES and Sanger sequencing revealed that the child has harbored compound heterozygous variants of the FBP1 gene, including a de novo nonsense variant c.778G>T (p.G260*) in exon 6 and a maternally derived missense variant c.923C>G (p.P308R) in exon 7. The c.923C>G was known as a likely pathogenic variant, while c.778G>T has not been included in the databases such as HGMD, ClinVar, 1000 Genomes, ExAC, dbSNP, and gnomAD. Protein structure prediction shows that the c.778G>T (p.G260*) variant may result in a premature termination codon, resulting in loss of a β-fold in a core region, which may significantly reduce the stability of its protein product and affect its function. Based on the ACMG guidelines, the c.778G>T (p.G260*) variant was rated as likely pathogenic (PVS1_Strong+PM2_Supporting+PP4+PM6). Literature review has identified 32 patients from 23 Chinese families with FBP1D due to FBP1 gene variants. Together with the case reported in this study, in total 33 patients were analyzed. Among them, 22 cases were males (66.7%) with hypoglycemia, metabolic acidosis, vomiting, seizures, hyperlactatemia, and ketosis as the primary clinical phenotypes. After treatment, only 1 case (3.0%) died due to cerebral hernia, while the remaining 32 (97.0%) had favorable outcomes. Four cases (12.1%) exhibited developmental delay. A total of 66 FBP1 gene variant sites were identified, which involved 22 variant types, predominantly missense mutations (31 gene variant sites). These variants were mainly located in exon 7 of the gene (25 variant sites), with c.490G>A (16.7%, 11/66), c.960_961insG (19.7%, 13/66), c.355G>A (12.1%, 8/66), and c.704delC (9.1%, 6/66) being the most common variants. CONCLUSION The heterozygous variant of the FBP1 gene probably underlay the FBP1D in this child. Above finding has enriched the phenotypic and mutational spectrum of the FBP1 gene and provided a basis for genetic counseling and clinical decision-making.
Humans ; Fructose-1,6-Diphosphatase Deficiency/genetics* ; Fructose-Bisphosphatase/genetics* ; Male ; Exome Sequencing ; Mutation ; Female ; Child

OBJECTIVE: To explore the clinical characteristics and genetic variants underlying Hereditary coagulation factor V (FV) deficiency in two Chinese pedigrees. METHODS: Seventeen individuals from three generations of the two pedigrees affected with FV deficiency whom had visited Taizhou Hospital of Zhejiang Province respectively in March and June 2024 were recruited as study subjects. One hundred healthy individuals undergoing physical examinations have served as the controls. Relevant coagulation parameters were measured. Thrombin generation was assessed using the calibrated automated thrombogram (CAT) assay. All exons and flanking regions of the F5 gene were amplified by PCR and directly sequenced. Candidate variants were analyzed for evolutionary conservation and potential pathogenicity, and their effects on protein structure were predicted. This study was approved by the Medical Ethics Committee of Taizhou Hospital of Zhejiang Province (Ethics No.: 20230722). RESULTS: The FV activity (FV: C) and antigen levels (FV: Ag) of both probands showed concurrent decrease. By thrombin generation assay, both the lag time ratio and time to peak ratio were significantly increased. Genetic analysis revealed that proband A carried compound heterozygous missense variants c.911G>A (p.Gly304Glu) and c.1238T>C (p.Met413Thr), whilst Proband B carried compound heterozygous missense variants c.1258G>T (p.Gly420Cys) and c.1538G>A (p.Arg513Lys) of the F5 gene. Conservation analysis revealed that the amino acid residues p.Gly304, p.Gly420, and p.Arg513 are highly conserved across various species. Online bioinformatics tools predicted that both the p.Gly304Glu and p.Gly420Cys variants are pathogenic. Protein modeling demonstrated that all four variants can result in alterations of protein structure or disruption of hydrogen bonding. CONCLUSION FV deficiency in these two pedigrees can be attributed to the compound heterozygous variants p.Gly304Glu/p.Met413Thr and p.Gly420Cys/p.Arg513Lys of the F5 gene.
Adult ; Female ; Humans ; Male ; Middle Aged ; China/ethnology* ; Factor V/chemistry* ; Factor V Deficiency/genetics* ; Heterozygote ; Pedigree ; East Asian People/genetics*

OBJECTIVE: To explore the phenotypic and genotypic characteristics of a Chinese pedigree affected with Hereditary coagulation factor XI (FXI) deficiency. METHODS: A female patient with FXI deficiency and her family members (five individuals from three generations) who presented at Quanzhou First Hospital Affiliated to Fujian Medical University on September 19, 2024 due to diarrhea and fever were selected as study subjects. A retrospective study was conducted to collect the patients' clinical data. Peripheral venous blood samples were collected from the patient and her family members. Genomic DNA was extracted, followed by sequencing of all exons and flanking sequences of the F11 gene. Candidate variants were validated by Sanger sequencing of the family members, and their pathogenicity was classified according to the guidelines of the American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of Quanzhou First Hospital [Approval No.: Quanyi Lun (2024) K281]. RESULTS: The patient exhibited significantly prolonged activated partial thromboplastin time (APTT) of 80.9 seconds, while FXI activity (FXI:C) and FXI antigen (FXI:Ag) levels were extremely low (2% and 3%, respectively). Genetic analysis revealed that the proband harbored homozygous c.896C>G (p.Thr299Ser) missense variant in exon 9 of the F11 gene, for which her son was heterozygous. The variant was located in a highly conserved domain. Although Mutation Taster predicted it as a polymorphism, SIFT, PolyPhen-2, and LRT analyses suggested it to be likely pathogenic. Protein modeling indicated that the p.Thr299Ser variant may alter the hydrogen bonds between amino acids, thereby affecting the structure and function of the FXI protein. According to the ACMG guidelines, c.896C>G was rated as a likely pathogenic variant (PM1+PM2_Supporting+PP1_Strong+PP3+PP4). CONCLUSION The c.896C>G (p.Thr299Ser) missense variant of the F11 gene probably underlay the FXI deficiency in this pedigree. Above finding has enriched the mutational spectrum of the F11 gene and provided a basis for genetic counseling and prenatal diagnosis for this family.
Adult ; Female ; Humans ; Male ; Middle Aged ; China/ethnology* ; Factor XI/chemistry* ; Factor XI Deficiency/genetics* ; Homozygote ; Pedigree ; Retrospective Studies ; East Asian People/genetics*

OBJECTIVE: To investigate the molecular pathogenic mechanisms of a family with hereditary factor Ⅶ (FⅦ) deficiency. METHODS: A family (3 generations, 12 members) with hereditary FⅦ deficiency, in which the proband presented with menorrhagia and was admitted to the First Affiliated Hospital of Wenzhou Medical University in April 2023, was selected as the study subject. Clinical data of the family members were collected. Peripheral venous blood samples were collected from all 12 members for routine coagulation tests and genomic DNA extraction. All exons and flanking sequences of the F7 gene were amplified by PCR and analyzed by Sanger sequencing. Thrombin generation assay was performed to evaluate the coagulation potential of the proband and her parents. Multiple online bioinformatics software tools were used to analyze the conservation and pathogenicity of candidate variants identified in the proband. The pathogenicity of variant was classified according to the Standards and Guidelines for the Interpretation of Sequence Variants released by American College of Medical Genetics and Genomics (ACMG) (hereinafter referred to as ACMG guidelines). Homology modeling of the variant FⅦ protein was performed using homology modeling (SWISS-MODEL). Amino acid sequence alignment between wild-type and variant FⅦ proteins was conducted using MEGA v7, and spatial conformational differences were analyzed using PyMOL to assess the potential impact of the F7 gene variants on the structure and function of the FⅦ protein. This study was approved by the Ethics Committee of the First Affiliated Hospital of Wenzhou Medical University (Ethics No.: KY2022-R193). RESULTS: Coagulation tests showed that the proband's prothrombin time (PT) was significantly prolonged to 33.1 s, and both factor Ⅶ activity (FⅦ:C) and antigen (FⅦ:Ag) levels were reduced to 2%. Her parents, eldest sister, second sister, younger brother, and four children all showed mildly prolonged PT, with FⅦ:C and FⅦ:Ag levels approximately 50% of normal. Genetic sequencing identified compound heterozygous variants in the F7 gene of the proband: a heterozygous missense variant c.722C>A (p.Thr241Asn) in exon 7, and a heterozygous deletion variant c.1261_1261delA (p.Ile421Ser*fs75) in exon 8. Retrieval from domestic and international databases found no previous reports of the latter variant, suggesting it is novel. Familial co-segregation analysis confirmed that these variants were inherited from her father and mother, respectively. The thrombin generation assay demonstrated that the proband had a significantly decreased peak thrombin height (peak ratio: 29.5%), significantly increased thrombin lag time ratio and time-to-peak ratio (3.03 and 2.93, respectively), but only a mildly decreased endogenous thrombin potential (ETP) ratio of 90.7%. Online bioinformatics analysis indicated that threonine-241 (p.Thr241) in the FⅦ protein was not conserved, while isoleucine-421 (p.Ile421) was highly conserved. Both the p.Thr241Asn and p.Ile421Serfs*75 variant sites in the proband's F7 gene were predicted to be pathogenic. According to the ACMG guidelines, the p.Thr241Asn (PM3+PP1+PP3+PP4+PP5) and p.Ile421Ser*fs75 (PM2+PM4 +PP1+PP3+PP4) variants were both classified as "likely pathogenic". Structural analysis of the FⅦ protein indicated that the p.Ile421Ser*fs75 frameshift variant led to the substitution of Cysteine-428 by Alanine, preventing the formation of a critical disulfide bond between amino acid residues 400 and 428 present in the wild-type FVII protein. CONCLUSION The compound heterozygous variants p.Thr241Asn and p.Ile421Ser*fs75 in the F7 gene are likely the genetic etiology responsible for the reduced FⅦ levels in this hereditary FⅦ deficiency family.
Adult ; Female ; Humans ; Male ; Middle Aged ; China ; Factor VII/chemistry* ; Factor VII Deficiency/genetics* ; Heterozygote ; Mutation ; Pedigree ; East Asian People/genetics*

OBJECTIVE: To analyze the phenotype and genotype of a family with hereditary coagulation factor Ⅹ (FⅩ) deficiency and preliminarily explore its molecular pathogenesis. METHODS: A hereditary FⅩ deficiency pedigree presented at the First Affiliated Hospital of Wenzhou Medical University on August 13, 2024 was selected as the study subject. Coagulation parameters of the proband and her family members (7 individuals from 3 generations) were measured using a one-stage clotting assay. All of the 8 exons and flanking sequences of the F10 gene were amplified by PCR and directly sequenced. Bioinformatics software was used to analyze the functional impact and pathogenicity of the variant proteins, as well as the spatial conformational changes and evolutionary conservation of the mutation sites. This study has been approved by the Medical Ethics Committee of the First Affiliated Hospital of Wenzhou Medical University (Ethics No.: KY2022-R193). RESULTS: The proband exhibited significantly abnormal prothrombin time (PT, 33.3 s), activated partial thromboplastin time (APTT, 47.7 s), and FⅩ activity (FⅩ:C, 3%), while other coagulation parameters remained normal. The plasma thromboplastin generation test (PTGT) demonstrated that the proband and her children had lower thromboplastin generation levels compared with the healthy control group, and the proband's thromboplastin generation capacity was more severely impaired. Genetic analysis revealed that the proband, her daughter, and grandson have all harbored a heterozygous missense variant c.212T>C (p.Phe71Ser) in exon 2 of the F10 gene, which was located in the β-sheet core region of the Gla domain. The variant has altered surrounding hydrogen bonds and disrupted calcium-binding sites. Additionally, the proband, her son, and granddaughter have all carried a heterozygous missense variant c.1270G>T (p.Val424Phe) in exon 8, which increased the side-chain volume, leading to steric hindrance in the catalytic domain and impaired coagulation function. Bioinformatics analysis confirmed that both p.Phe71Ser and p.Val424Phe were pathogenic variants, with Phe71 and Val424 being highly conserved residues. CONCLUSION The reduced FⅩ levels in this hereditary FⅩ-deficient family may be attributed to the heterozygous missense variants c.212T>C (p.Phe71Ser) in the exon 2 and c.1270G>T (p.Val424Phe) in the exon 8 of the F10 gene.
Humans ; Female ; Male ; Pedigree ; Adult ; Heterozygote ; Mutation ; Middle Aged ; Factor X/genetics* ; Exons ; Factor X Deficiency/genetics*