A Newly Detected C.180 + 1G > A Variant Causes a Decrease of FGA Transcription in Patients with Congenital Hypo-Dysfibrinogenemia

Congenital hypo-dysfibrinogenemia is a rare autosomal dominant or co-dominant genetic disorder. This study was designed to analyze the clinical phenotype and genetic mutations of a patient with congenital hypo-dysfibrinogenemia. Prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), and D -dimer were measured using an automated coagulation analyzer. Fibrinogen (Fg) was assessed by the Clauss and PT-Fg methods. Sanger sequencing was conducted to identify the mutations in FGA , FGB , and FGG genes. The proband and proband’s mother, maternal uncle, and maternal grandfather exhibited a prolonged TT, decreased Clauss Fg and PT-Fg, and normal PT, APTT, and D -dimer without abnormalities in liver and kidney function. The ratio of Clauss Fg to PT-Fg was less than 0.7. A novel c.180 + 1G > A mutation was detected in FGA gene by Sanger sequencing in the proband and proband’s mother, maternal uncle, and maternal grandfather. FGA c.180 + 1G > A variant leads to decreased transcription of FGA . The patient was diagnosed with congenital hypo-dysfibrinogenemia presenting a novel c.180 + 1G > A mutation in FGA , causing a decrease in FGA transcription in proband’s peripheral blood.