The MILE (Microarray Innovations In LEukemia) study pre-phase

An international standardization program towards the application of gene expression profiling in routine leukaemia diagnostics: The MILE study pre-phase. A total of 11 laboratories from three continents performed 204 analyses using a whole-genome expression microarray. In an effort to standardize the microarray procedure, each participating centre was equipped with identical hardware, software, and reagents. Designated study operators received intensive individual training on the sample preparation protocol. Keywords: Standardization and reproducibility of microarray analysis This study is part of the MILE Study (Microarray Innovations In LEukemia) program, headed by the European Leukaemia Network (ELN) and sponsored by Roche Molecular Systems, Inc. Each laboratory prepared two separate cell line total RNA samples, as well as three replicate leukaemia patient lysates in two distinct project stages: (i) a five-day course of protocol training, and (ii) independent proficiency testing. Using unsupervised, supervised, and r² correlation analyses we demonstrated that microarray analysis can be performed not only with remarkably high intra-laboratory reproducibility but also with comparable quality and reliability between eleven distinct laboratories.