The vast majority of the new sequences are also mixture, either because samples had D225G and D225N, or had one or the other along with wild type. These combinations may facilitate spread by allowing for infections in both the upper respiratory tract as well as the lower respiratory tract.
Moreover, a pair sample from a patient in Kathmandu had D225G (as a mixture) in the nasal sample, while the throat sample had a wild type RBD. Similarly, the samples in Ukraine were from multiple oblasts and represented multiple sub-clades. Most sub-clades had at least one sample lacking the RBD change, further supporting acquisition of the position 225 changes via recombination.