marked differences between the mutagenic efficiency of n-methyl-n-nitrosourea ( mnu ) , a potent carcinogen , methyl methane sulphonate ( mms ) and dimethyl sulphate ( dms ) , both weak carcinogens , have been reported at the hypoxanthine-guanine phosphoribosyltransferase ( hgprt ) and ouabain loci in v79 cells .
C1708726
loci
C0007634
cells