Alterations in the mutagenicity and mutation spectrum induced by benzo[a]pyrene instilled in the lungs of gpt delta mice of various ages

Table 4 Specific mutant frequency of G:C to A:T transition and G:C to T:A transversion on gpt gene from the lung of B[a]P-instilled and control mice

Type of mutation in the gpt gene	Control (months)			B[a]P (months)
	3	11	24	3	11	24
	Specific mutant frequency* (×10⁻⁵)
G:C → A:T	0.27	0.44	0.35	0.25	0.42	0.92**
G:C → T:A	0.12	0.18	0.14	1.39	0.40	0.41

*Specific mutant frequency = [Average mutant frequency in Table 1] × [% mutant of G:C to A:T transition or G:C to T:A transversion of corresponding group in Table 2]
**P < 0.001 (Chi-square test) for comparison between B[a]P-instilled mice and age-matched control mice

ISSN: 1880-7062