we conclude that ( 1 ) chemicals that induce a high proportion of chromosomal mutants , as detected at the tk locus in earlier studies , also induce single gene mutations at the ouabain-resistance locus and ( 2 ) a bimodal distribution of mutant colony sizes in soft-agar medium after short expression periods may be a distinctive characteristic of the 3.7.2c l5178y cell line and is not confined to the tk locus .
C0008633
chromosomal
C1708726
locus