FGA (Fibrinogen α)

FGA encodes the alpha chain of fibrinogen, the soluble plasma protein that fibrin clots are built from.

Function

Fibrinogen is a 340 kDa hexamer of two each of three chains (α, β, γ), made by the liver and circulating at 2-4 g/L - the third-highest plasma protein concentration. Thrombin cleaves short peptides from the α and β chains, the molecules polymerize into fibrin strands, and Factor XIII cross-links them into the mesh that stops bleeding. The acute-phase response raises fibrinogen several-fold (IL-6 drives hepatic production), which is why fibrinogen is a clinical inflammation marker. Fibrin is also the provisional scaffold of wound