Cells may be analog, but DNA is digital -- with error correction even (or error deletion at least). I don't know the details of the epigenome, so maybe that isn't digital?
DNA is not digital though. It has a geometrical structure (independent of epigenetic modifications) that is dependent on a slew of environmental factors that alters it’s meaning. The computer programmer’s incessant need to reduce complexity to bits needs to stop.
DNA is literally digital: it is a quaternary system based on four values: AT, TA, CG, and GC. Those are the only four values possible within the system. If you want to claim it's not (without resorting to the epigenome) then nothing is digital.
