Patent ID: 6984772

Claim:
A method for producing biologically active fibrinogen comprising: providing a transgenic non-human mammal whose genome comprises a first DNA segment encoding a first DNA encoding a heterologous fibrinogen Aα chain, a second DNA segment encoding a second DNA encoding a heterologous fibrinogen Bβ chain, and a third DNA segment encoding a third DNA encoding a heterologous fibrinogen γ chain, wherein each chain is derived from the same species, and wherein each of said first, second and third segments is operably linked to a cis-acting, expression promoter-containing regulatory sequence required for its expression in a mammary gland of a female transgenic non-human mammal; allowing the expression of said first, second and third DNA segments and the production of milk containing biologically active fibrinogen in said female mammal; collecting milk from said female mammal; and recovering the biologically active fibrinogen from the milk.