TABLE 1.

Knockout analysis of band IV with different transfecting plasmids

Recipient cell line	% of cell lines exhibiting targeted knockout with:		No. of cell lines obtaineda with:
	pLew13-IV- k/o(hygro)	pLew13-IV- k/o(G418)	pLew13-IV- k/o(hygro)	Control construct (hygro)b	pLew13-IV- k/o(G418)	Control construct (G418)c
Wild typed	100	100	19e	23	12f	17
First allele IV knockout (with G418r gene)	0		4g	24
First allele IV knockout (with hygror gene)		0			8g	17

^aNumber of lines obtained out of 24 possible (number of microtiter wells seeded with transfected cells). 

^bPlasmid pLew128. 

^cPlasmid pLew13. 

^dLine 427. 

^eTen of these lines were analyzed by PCR. 

^fFive of these lines were analyzed by PCR. 

^gAll of these lines were analyzed by PCR.