Genetic analysis and clinical features of a pedigree affected with hereditary coagulation factor Ⅶ deficiency caused by compound heterozygotic mutations
10.3760/cma.j.issn.1003-9406.2019.10.014
- VernacularTitle: 一例复合杂合突变导致的遗传性凝血因子Ⅶ缺陷症患者的临床与遗传学分析
- Author:
Yanhui JIN
1
;
Lihong YANG
;
Feng ZHANG
;
Meina LIU
;
Kankan SU
;
Xiaolong LI
;
Mingshan WANG
Author Information
1. Center of Laboratory Medicine, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325015, China
- Publication Type:Clinical Trail
- Keywords:
Coagulation factor Ⅶ;
Genetic defect;
Compound heterozygous mutation;
Coagulation disorder
- From:
Chinese Journal of Medical Genetics
2019;36(10):1006-1009
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To detect potential mutations of the coagulation factor Ⅶ (F7) gene in a pedigree affected with hereditary FⅦ deficiency and explore its molecular pathogenesis.
Methods:The FⅦ antigen (FⅦ∶Ag) was analyzed by an enzyme-linked immunosorbent assay (ELISA) method. Prothrombin time (PT), FⅦ activity (FⅦ∶C) and other coagulant parameters were quantified with an one-stage clotting assay. The F7 gene was amplified by PCR and sequenced. Mutational sites were confirmed by reverse sequencing. Impact of amino acid substitution was assessed using SIFT and PolyPhen-2 software. Structure of the mutant protein was analyzed using Swiss-pdb Viewer software based on the three-dimensional structure in the Protein Data Bank.
Results:The propositus had prolonged PT (36.3 s), with FⅦ∶C and FⅦ∶Ag significantly reduced to 2% and 44%, respectively. Her father, mother, younger sister and daughter had slightly prolonged PT and reduced FⅦ∶C (86%-120%). The FⅦ∶Ag of her father and younger sister were also reduced. DNA sequencing revealed that the propositus has carried compound heterozygous mutations (Lys341Glu and IVS6-1G>A) of the F7 gene. Her father and younger sister were heterozygous for the IVS6-1G>A mutation, while her mother and daughter were heterozygous for the Lys341Glu mutation. Bioinformatics analysis indicated that Lys341Glu mutation may affect the stability and function of the FⅦ protein.
Conclusion:The Lys341Glu and IVS6-1G>A mutations probably underlie the reduced activity of FⅦ in this pedigree.
