Dear Sergei,

As requested, I'm using the bulletin board, rather than walking down the corridor to hassle you...

For a number of analyses (see the following message re: compartmentalization), it is useful to define groups of sequences. These may be simple - just defining a list of group (e.g. for HIV sequences, multiple patients or different compartments from the same patient), hierarchical (e.g. multiple patients, with compartments), or crossed. It would be nice to have (a) a syntax to define these different structures and (b) a GUI widget to define them.

Best
Simon