Length read

[pingu]

Hello!
I am using 454 Roche Junior and I would be trim my primers. How much it must be length a read for be accepted before both trimming and after?
Thank you in advance

[Brian Bushnell]

That depends on what you're doing. For small RNA studies, for example, even 17bp is useful. For most other cases, you'd want longer reads. So, what's the experiment?