Using the affy library, I did an RNA degradation plot for 5 mu74Av2 mouse chips and it generated the figures below. I do not have anything to measure this against - if someone has some figures on what "degraded" RNA looks like (and/or some thresholds), and a representative plot I would be appreciative. slope -0.0201 -0.236 -0.228 -0.0884 -0.209 pvalue 0.858 0.0517 0.0751 0.44 0.115 Thanks BillK