Genechip Animation

Definition

An array of short DNA oligonucleotides (usually 20 nucleotides long) synthesized onto a solid support by photolithography, each of which corresponds to a single gene.

  Subscribe in a reader

Stephen Fodor developed a technique called GeneChip probe arrays where he built the sequences he wanted. These GeneChip arrays are printed on special glass.DNA Sequence are built up using light directed chemical synthesis. First, a substrate with a nucleotide is fixed onto the chip at specific positions.The nucleotide has a protecting group(X) that blocks polymerization. This protector group is photolabile and is released on exposure to UV light. Without the protector, polymerization and chain build-up occur.A filter is added to the chip so that only some of the nucleotides are exposed to light. These deprotected groups are then free to add the next nucleotide to the chain.By alternating the position of the filter, Fodor can build a GeneChip with an array of different sequences about 20 nucleotides long.Fodor added a cDNA probe to the GeneChip.He could simultaneously assay tens of thousands of different sequences at the same time.