<;P>;PROBLEM TO BE SOLVED: To provide a new method for producing a protein containing a Gla residue. <;P>;SOLUTION: A transgenic fowl is obtained by a method for infecting the heart or blood vessel formed in an embryo of a fowl in the initial stage of embryo development with a retrovirus vector containing an extraneous gene by micro-injection and hatching the embryo. Thereby, the protein containing the Gla residue is produced. <;P>;COPYRIGHT: (C)2007,JPO&INPIT