Ron Davis and I were studying plant transcription factors in 1990, but progress was slow and arduous because the gene expression tools were so primitive. We conceived of the DNA microarray in 1993 to speed up gene expression analysis by combining biology and high technology. We adapted Affymetrix VLSIPS technology to synthesize yeast microarrays, and measured gene expression in yeast cells by hybridizing fluorescent probes derived from mRNA. The image shows the very first microarray experiment, with colored locations on the microarray providing readouts of expressed yeast genes. We worked frantically to improve the technology, and generated the first quantitative DNA microarray data using robotically printed plant cDNAs amplified by PCR. Science magazine kindly published our work (M. Schena et al., "Quantitative monitoring of gene expression patterns with a complementary DNA microarray," Science, 270:467-70, 1995), and since then the technology has exploded."
--Mark Schena
