Figure 2. DNA microarray--Lymphochip. (Center) Lymphochip version 8.0, printed on a coated glass microscope slide using a 32-tip printing head, contains 17,856 cDNA clones (overhead illumination) (14). (Left) U.S. penny, for scale. (Right) Scanned image demonstrating differential hybridization of Cy3- and Cy5-labeled cDNA to this microarray. (Illustration by A. Alizadeh, M. Eisen, and P. Brown, Stanford University; and L. Staudt, National Cancer Institute).