HI! All: I am used an old version of pymol. When I selected C5* in the backbone of DNA , pymol will select two atoms, one is C5* on backbone the other is C5 on base pair. My expression is select (chain/residue number/C5*). If you are using the newly version of pymol, would you like to try the expression as above and tell me whether this little bug has been corrected? Happy new year! Fei Xu