Table 2. Generation of founder knock-out lines by ends-out targeting.

Target Gene	G418 (mg/ml)	Targeting Virgins Females	Screening Cross Progenya	Preliminary Candidates	On Target Chr.	Genetically Verified	PCR Verified	HR Frequencyb
dArf6	0	6,000	∼7×105	315	30/315	5/30d	5/5	∼7×10−6
	0.20	6,000	∼6.7×104	221	43/221	23/43d	6/6	∼3.4×10−4
Dscam-N	0	16,000c	∼1.6×105	71	50/71	23/50e	2/2	∼1.4×10−4
	0.20	(16,000)c	∼3.3×104	557	399/557	162/399e	5/5	∼4.9×10−3
Dscam-C	0	9,400c	∼1.9×105	23	11/23	3/11e	3/3	∼1.6×10−5
	0.20	(9,400)c	∼2.2×104	42	12/42	3/12e	3/3	∼1.3×10−4

^a.Total estimated number of screening cross progeny screened in each targeting experiment. Because progeny of multiple vials or bottles were pooled and screened together, we did not register the clonality of the preliminary candidates. We assumed that each targeting mutant obtained was due to a distinct targeting event, based on the low HR frequency observed.

^b.Since all female candidates were discarded in targeting experiments, the adjusted HR frequency should be twice higher than listed here.

^c.Screening crosses were set up on the normal food first, then transferred to G418 food after two days.

^d.A dArf6^ΔKG#1 deletion allele generated by P-excision was used for complementation assays [7].

^e.Null allele of P{PZ}Dscam⁰⁵⁵¹⁸ (BL#11412) [13] was used for complementation assays.