. 2006 Jan 11;103(4):1036–1040. doi: 10.1073/pnas.0510177103

Table 2. Comparison between construct 1 and 2 of frequencies in targeting and expression of human β^A-globin gene after repair.

			Expression of hemoglobin A in targeted clones
Targeting construct	Targeting frequency	Crossover frequency at β⁶	Yes	No
Construct 1	8/74	7/8	6, 13, 34, 42, 51	5, 40
Construct 2	4/50	1/4	41	11, 43, 44

Table 2. Comparison between construct 1 and 2 of frequencies in targeting and expression of human βA-globin gene after repair.