The tautomeric T can pair with G, rather than A, so G will be incorporated into the new strand where there was an A in the old strand. Similarly, if A is in its tautomeric state when the DNA is being replicated then it will pair with C, rather than T, so the new strand has C, where the old strand had T (figure 7.3). In either case, the newly formed DNA strands will carry mutations—changes in the DNA sequence that will be inherited by progeny.
