Dear Moo, You can do it with two commands select #0:51 ~select #0:51a or all in one command with select #0:51 & ~ #0:51a where & = AND (intersection) and ~ = NOT (this approach would be the more convenient if you were using commands other than select, such as "color" "display" etc.) I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. meng@cgl.ucsf.edu UCSF Computer Graphics Lab and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco http://www.cgl.ucsf.edu/home/meng/index.html On Jul 8, 2005, at 10:53 AM, Moo Cow wrote:

I would be very grateful for advice. Some coordinates contain residue 51 residue 51A (a residue with an insertion code) If I select #0:51 then both residues are selected. Is there any way to persuade chimera to just select residue 51, but not 51A ? Many thanks