These include sequences with the capacity to adopt H-DNA [39], G-quadruplexes [37] and Z-DNA conformations
[92], and each of these non-B DNA elements individually has been
shown to be mutagenic in simplified models. However, the ability
to demonstrate the extent to which one or another structure
within this sequence impacts the formation of another and/or is
solely responsible for the induced genetic instability in vivo remains
a challenge.