Single transitions C<-->G, U<-->A

Transitions of type типа C<-->G, U<-->A between the second bases connect triplets within octets O₁ - O₈ from top to down, for example: CCC<--->CGC, CUC<--->CAC.

Fig. 12, b. Single transitions of type C<-->G, U<-->A between the second bases of triplets.