Hello,

I have a large DGEList which (should) contain 8 groups, however within Samples the Group factor level is only 1. Does anyone know how I can redefine my groups?

The data was sent to me via an .rda file which I then read in to R.

Any help would be greatly appreciated, Many thanks.

The 'samples' list item of a DGEList is just a data.frame, so you can do whatever you want to it and put it back into the DGEList.

samps <- dglst$samples

## do stuff to it
dglst$samples <- samps

It's up to you to ensure that the 'samples' list item makes sense in the context of your experiment.

Just use standard R language. If dgelst is the DGEList object, then

dgelst$samples$group <- YourGroupFactor