The barcoding was done using the following tags at the beginning of each read: CCT, AAT, GGT, CGT (see supplementary material of Cronn2008). The settings in the dialog should thus be as shown in figure 22.27.
Click next to the "Set barcode options" dialog and use the Add button) to specify the bar codes as shown in figure 22.28.
With this data set we got the four groups as expected (shown in figure 22.29). The Not grouped list contains 445,560 reads that will have to be discarded since they do not have any of the barcodes.