Microarrays

Microarrays provide a way to study the expression of many genes or even the whole genome at once. These "chips" are made by affixing thousands of different PCR products, cDNAs or oligonucleotides as rows of dots on to a glass or plastic base, using robotics.

Next, the test DNA (typically cDNA) which has been fluorescently labelled, is hybridized to the chip, where it binds to any complementary sequences affixed to the chip. A scanner reads the amount of fluorescence at each "feature", and a computer analyzes the pattern of the expressed genes.

 

A picture of the Q-bot robotic system for producing microarrays, and 2 examples of partial microarray chips.