Related Topics
Timelines: 1994
Prev : Next 
The GeneChip®
Genetics and electronics converge
In conjunction with Stanford’s Department of Biochemistry, researchers at Affymetrix invent, manufacture, and market the GeneChip®, a small glass or silica microchip that serves as a DNA microarray. Each chip contains 64,000 sites that contain purified, single-stranded DNA oligonucleotide probes fixed to the surface. Tests are conducted by adding samples of target cDNA sequences labeled with fluorescent or chemoluminescent dyes. The chip is washed, leaving only hybridized probes and targets with labels that can be excited, detected, measured, and recorded by laser scanners. The intensity of the signal is a quantitative measure of levels of hybridization and gene expression or identity. A survey of the entire chip yields a broad gene expression profile. The high-volume capacities of DNA microarrays vastly accelerate clinical and laboratory work in genetics, biochemistry, and molecular biology.
