Patent ID: 8021867

Claim:
A recombinant meganuclease having altered cleavage specificity relative to the wild-type I-CreI meganuclease of SEQ ID NO: 1, comprising a polypeptide having at least 85% sequence identity to residues 2-153 of the I-CreI meganuclease of SEQ ID NO: 1, which differs from residues 2-153 of the I-CreI meganuclease of SEQ ID NO: 1 by: (a) at least a first specificity-altering amino acid modification at a position corresponding to a position of SEQ ID NO: 1 selected from the group consisting of positions 24, 26, 28, 30, 32, 33, 38, 40, 42, 44, 46, 66, 68, 70, 75, 77, 79 and 139; and (b) at least a second specificity-altering amino acid modification at a position corresponding to position 26 or 77 of SEQ ID NO: 1, wherein said second specificity-altering amino acid modification is a substitution selected from the group consisting of Q26E, Q26K, Q26S, I77E, I77Q, I77R and I77S; and (c) at least a third amino acid modification affecting heterodimer formation selected from the group consisting of K7D, K7E, E8K, E8R, K57D, K57E, E61K, E61R, K96D and K96E.