Figure 6.

An ideal reference RNA sample will provide detectable hybridization above background for as broad as possible representation of the arrayed genes. The histogram shows the percentage of array elements with detectable signals in both the Cy3 and Cy5 channels for a series of self-self hybridizations representing all of the primary cell lines used in this study, the Stratagene universal reference RNA, and RNA pools created on the basis of our analysis. TP-1 consists of equal amounts of CaCO2 (colon), KM12L4A (colon), and OVCAR3 (ovary) cell lines. TP-2 consists of equal amounts of CaCO2 (colon), KM12L4A (colon), and U118 MG (brain) cell lines. Mean values with 1 SD as the error bars are plotted for the samples that were assayed more than once. CaOV3, HCT-116, KM12L4A, NT2/D1, and SW480 cell lines were assayed in triplicate, and Stratagene and TP-1 pools were hybridized in duplicate.