FGA
Chr 4ARADfibrinogen alpha chain
Also known as: AMYLD2, Fib2
This gene encodes the alpha subunit of fibrinogen, a blood coagulation factor that is cleaved by thrombin to form fibrin for blood clot formation and wound healing. Mutations cause congenital afibrinogenemia, hypodysfibrinogenemia, and dysfibrinogenemia (typically autosomal recessive) as well as hereditary systemic amyloidosis (autosomal dominant). The gene shows very low constraint against loss-of-function variants, reflecting the viability of individuals with complete fibrinogen deficiency.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly tolerant — LoF variants common in population
Tolerant to missense variation
The highest-scoring mechanism for this gene is dominant-negative.
Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.
Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
FGA · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
SWOC Activities on Balance, Gait and Endurance in Children With Autism Spectrum Disorder
RECRUITINGGenomics of Fibrin Clot Structure in Patients With Constitutional Dysfibrinogenemia
ACTIVE NOT RECRUITINGExternal Resources
Links to major genomics databases and tools