Table 4. Gene targeting by Ppapt-KO mismatch vectors in Ppsrs2-KO.

Strain	Mismatch	HygR	2-FAR	%GT	RTF(%)
Ppsrs2-KO	0% mismatch	248	52	41.9*	1.12
Ppsrs2-KO	1% mismatch	48	13	16.7	0.10
Ppsrs2-KO	2% mismatch	17	5	5.9	0.10
Ppsrs2-KO	3% mismatch	26	8	0	0.006

*GT efficiencies vary, depending on the nature of the targeting construct (Kamisugi et al., 2005). Thus the GT frequency obtained with this vector cannot be compared with that obtained with the different PpAPT targeting vector used for the experiments reported in Table 3.