Patent ID: 7767799

Claim:
An isolated DNA molecule encoding a mutated human IFNα2 polypeptide, said IFNα2 polypeptide comprising: at least three mutations selected from the group consisting of (a) mutation of the histidine at position 57 to a residue selected from the group consisting of alanine, tyrosine, and methionine; (b) mutation of the glutamate at position 58 to a residue selected from the group consisting of alanine, asparagine, and aspartate; (c) mutation of the glutamine at position 61 to a residue selected from the group consisting of alanine, serine and leucine; (d) mutation of the glutamate at position 159 to lysine; (e) mutation of the serine at position 160 to arginine; and (f) mutation of the arginine at position 162 to lysine; or at least four mutations selected from the group consisting of: (g) mutation of the asparagine at position 65 to alanine; (h) mutation of the leucine at position 80 to alanine; (i) mutation of the tyrosine at position 85 to alanine; (j) mutation of the tyrosine at position 89 to alanine; (k) mutation of the glutamate at position 159 to lysine; (l) mutation of the serine at position 160 to arginine; and (m) mutation of the arginine at position 162 to lysine.