Table 2.

Mutations at codon 12 of H-ras and K-ras in mammary tumors induced by MeNU or EtNU in normal and ada-transgenic rats

	MeNU		EtNU
	Alkyltransferase status*
	Normal	Surplus (adatransgenic)	Normal	Surplus (adatransgenic)
H-ras codon 12	6/8†	6/10	0/12	0/7
K-ras codon 12	0/15	ND	0/12	0/3

ND, not determined. 

^*Mammary epithelia at carcinogen exposure. 

^†Number of tumors with mutant gene/number of tumors.