Functional genomics: Learning to think about gene expression data Roger Brent  Current Biology  Volume 9, Issue 9, Pages R338-R341 (May 1999) DOI: 10.1016/S0960-9822(99)80208-5 Copyright © 1999 Elsevier Science Ltd Terms and Conditions

Figure 1 A painting, Ken's light, by Andrea Way in 1993, bears a resemblance to the way gene expression data from microarrays are often represented. Current Biology 1999 9, R338-R341DOI: (10.1016/S0960-9822(99)80208-5) Copyright © 1999 Elsevier Science Ltd Terms and Conditions

Figure 2 A detail of the Andrea Way painting shown in Figure 1 reveals apparent connections among network elements. It thus symbolizes a level of functional understanding we would like to be able to use genomic data to reach. Current Biology 1999 9, R338-R341DOI: (10.1016/S0960-9822(99)80208-5) Copyright © 1999 Elsevier Science Ltd Terms and Conditions

Figure 3 A figure based on the data from [1] shows cluster representation of genes (listed on the right) whose transcription is induced immediately after the onset of yeast sporulation. In such representations [7][8], the value of a measurement is represented by its color, measurements deemed similar by some criterion are presented together and units of time are represented by successive blocks along the horizontal. These displays are now being used to facilitate, for example, inspection of the transcription patterns of genes whose transcription is induced under similar circumstances. Although these displays afford a step up from the raw data, they do not represent the information at a high enough level of abstraction to easily extract much meaning from it. Current Biology 1999 9, R338-R341DOI: (10.1016/S0960-9822(99)80208-5) Copyright © 1999 Elsevier Science Ltd Terms and Conditions