Table 2

hprt MRs and MnFs in the primary culture of normal mammary epithelium and two mammary carcinoma cell lines

Experiment no.Primary culture of normal mammary epitheliumPhIP12-1PhIP7-4
Final cell no. (×106)No. of mutantsNo. of mutationsMF (×10−6)MnF (×10−6)Final cell no. (×106)No. of mutantsNo. of mutationsMF (×10−6)MnF (×10−6)Final cell no. (×106)No. of mutantsNo. of mutationsMF (×10−6)MnF (×10−6)
11.200001.2544.33.41.0333.33.3
21.3110.90.91.1333.03.01.2554.74.7
31.100001.1332.92.91.1777.37.3
41.500001.1222.02.01.2221.91.9
51.200001.1554.74.71.1666.46.4
61.300001.1332.92.91.1777.07.0
71.2111.01.01.0444.34.30.96222.32.3
81.300001.1333.03.01.2332.92.9
91.200001.1222.02.01.2221.91.9
101.300000.93111.11.10.94556.06.0
111.400001.1554.74.71.2766.75.8
120.9900001.0444.24.21.2332.92.9
131.200001.1111.01.01.1111.01.0
141.2111.11.11.1554.94.91.2887.47.4
151.300001.0222.12.11.0555.45.4
161.200001.0333.13.11.2221.91.9
171.200001.1111.01.01.1111.01.0
181.300001.1555.05.01.1666.26.2
191.300001.0333.13.11.1444.04.0
201.200001.0111.01.01.1555.15.1
211.1111.11.11.1333.03.01.1222.12.1
221.300001.1111.01.00.95555.95.9
231.400001.1222.02.01.2110.90.9
241.400001.1211.91.01.1111.01.0
Total4469679392
Mean ± SE1.3 ± 0.020.17 ± 0.080.17 ± 0.081.1 ± 0.012.8 ± 0.282.8 ± 0.28a1.1 ± 0.024.0 ± 0.463.9 ± 0.45b
Plating efficiency (%)81 ± 5.294 ± 1.589 ± 4.4
MR (×10−7)1.48.211
  • a Differences between the primary culture of normal mammary epithelium are significant at P < 10−9.

  • b Differences between the primary culture of normal mammary epithelium are significant at P < 10−10.