7-Methylguanine is a metabolite of the natural purine base whose N9 position is available for chemical modifications.1 This genotoxic adduct can be generated by DNA methylation and has been used as a probe of protein-DNA interactions and for DNA sequencing methods.2 It is also considered to be a carcinogenic biomarker for cigarette smoking that is detectable in urine.3
1.Kozma, A., Ibá?ez, S., Silaghi-Dumitrescu, R., et al.7-Methylguanine: Protonation, formation of linkage isomers with trans-(NH3)2Pt(II), and base pairing propertiesDalton Trans.416094-6103(2012) 2.Lee, S., Bowman, B.R., Ueno, Y., et al.Synthesis and structure of duplex DNA containing the genotoxic nucleobase lesion N7-methylguanineJ. Am. Chem. Soc.130(35)11570-11571(2008) 3.Lee, H.L., Hsueh, Y.M., Chung, C.J., et al.Correlation between the urine profile of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone metabolites and N7-methylguanine in urothelial carcinoma patientsCancer Epigemiol. Biomarkers Prev.17(12)3390-3395(2008)