Vicki Brown wrote: [snip] ! Solution B (mine) ! ! $seq =~ tr/[A-Zatcgn]/n/c; ! $seq =~ tr/[a-zATCGN]/N/c; [snip] ! Anyone have a nicer solution? well, dropping the square brackets improves the appearance a teeny bit: $seq =~ tr/A-Zatcgn/n/c; $seq =~ tr/a-zATCGN/N/c; regards andrew ==== Want to unsubscribe from this list? (Don't you love us anymore?) ==== Well, if you insist... Send mail with body "unsubscribe" to ==== fwp-request@technofile.org