Hi All, The bug that was causing consistency problems with rma/justRMA and gcrma/justGCRMA has been fixed as of affy 1.4.23. Thanks again to Dick Beyer for pointing this out. Best, Jim James W. MacDonald Affymetrix and cDNA Microarray Core University of Michigan Cancer Center 1500 E. Medical Center Drive 7410 CCGC Ann Arbor MI 48109 734-647-5623