[Genetic Diagnosis and Phenotype Analysis for 3 Patients with Hereditary Coagulation Factor Ⅶ Deficiency].

OBJECTIVE: To investigate the gene mutations types and the clinical characteristics in 3 patients with hereditary coagulation factor Ⅶ deficiency. METHODS: The phenotype diagnosis was validated by detecting the coagulation parameters including prothrombin time (PT)，activated partial thromboplastin time (APTT), fibrinogen (FIB), FⅦ activity (FⅦ: C) and specific antigens (FⅦ: Ag) of proband and its family members. All exons, exon-intron boundaries, 5＇ untranslated regions and 3＇ untranslated regions of F7 gene were amplified with PCR. Potential mutations were detected by direct sequencing of purified PCR products. Suspected mutations were confirmed by sequencing of the opposite strand. RESULTS: A total of 5 different mutations were identified in 3 patients with hereditary coagulation factor Ⅶ deficiency and family members, including 4 misssense mutations and 1 splice site mutation. Out of 3 cases of hereditary coagulation factor Ⅶ deficiency 2 had double heterozygous mutation, I had homozygous mutations. Patient 1 had p.His408Gln with p.Arg413Gln double heterozygous mutations, her sister had p.His408Gln with p.Arg413Gln double heterozygous mutations, another one had p.His408Gln mono-heterozygous mutation, their correspo FⅦ: C were 5%, 3%, 75%. Patient 2 had p.Arg364Gln with p.His408Gln double heterozygous mutations, her brother had p.Arg364Gln with IVS6-1G＞A double heterozygous mutations, their corresponding FⅦ: C were 2.0%, 2.0%. Patient 3 had p.Arg337Cys homozygous mutation, FⅦ: C was 3.0%. CONCLUSION: A total of 5 different mutations were identified in 3 patients with hereditary coagulation factor Ⅶ deficiency, the p.His408Gln is a common mutation, the FⅦ: C and FⅦ: Ag have no correlation with clinical phenotypes.