To test its versatility, we extended the application of PCVA to a DNA system and introduced the single base PCVA (sbPCVA) analogous to saaPCVA. For the quite small and simple test system with 20 base pairs the construction of QM regions based on PCVA-calculated sensitivities did not significantly improve the reaction energy convergence compared to distance-based inclusion. Nevertheless, regarding the sensitivities, deviations from a clear distance-dependent trend have been observed. With that sbPCVA can be a helpful tool to at least estimate a reasonable QM region size to get consistent results especially when it comes to more complex DNA systems.