| Comments |
P.12872 right column 2nd paragraph: "The most abundant spontaneous single-strand DNA lesions (SSLs) are single-strand breaks (SSBs), apurinic/apyrimidinic (AP) sites, the oxidation products 8-oxoguanine (8-oxoG) and thymine glycol (TG), and some endogenous alkylation products, including 3-methyladenine (3-MA) (primary source 1, refs 15–20). [Investigators] estimated the rate of production of SSBs and AP sites in vivo at ≈600 per h and of 8-oxoG and TG at a minimum of ≈200 and 100 per cell per h, respectively (primary Source 1 and references therein). [They] do not have an estimate for the rate of production of 3-MA, but it seems to be an order of magnitude below that for SSBs and oxidation base products. The total rate of production of these SSLs is probably ≈1,000 per cell per h and, therefore, on the order of 5 × 10^3 per S phase, or 10^–6 per base pair of DNA per S phase. This rate is ≈100 times the rate calculated for production of endogenous double-strand
breaks (EDSBs) per cell during DNA replication [BNID ]." Note-in article units for SSBs and AP sites are "per hour" whereas should probably be "per cell per hour". |