GelEnter accepts any valid GCG sequence character.
Once you enter sequences into a project database, you can no longer edit them with GelEnter.
GelEnter
gcg2 21% gelenter seq02.dat
GelEnter adds fragment sequences to a fragment assembly project. It
accepts sequence data from your terminal keyboard, a digitizer, or
existing sequence files.
 "seq02"  593 nucleotides
 IUB/GCG       Meaning
    A             A
    C             C
    G             G
   T/U            T
    M           A or C
    R           A or G
    W           A or T
    S           C or G
    Y           C or T
    K           G or T
    V        A or C or G
    H        A or C or T
    D        A or G or T
    B        C or G or T
   X/N     G or A or T or C   
   ./~      gap character