Question

In 1997 Joseph DeRisi, Vishwanath Iyer, and Patrick Brown conducted an experiment on Saccharomyces cerevisiae using DNA microarrays. Describe their experiment, their hypothesis and their general findings from their study.

Answer 1

All these three scientists have worked on the technique known as the DNA microarray where the binding affinity of the gene sequence with its complementary attached on the microarray chip has been observed.

These scientists have a hypothesis to analyze the gene expression pattern in the respective species for the comparable data. Hence, the experiment which has been performed by them is as follows:

• They have considered the two species which are distinct from each other to analyze the altered expression pattern for the gene X
• Then the isolation of the RNA has been done from those species and allows the extracted RNA to undergo the reverse transcription to convert into the cDNA which is also known as complementary DNA which is complementary to RNA strand with the addition of Cy3 and Cy5 genes which are the fluorescence signaling molecules.
• Whenever the RNA1 that is cDNA1 with Cy3 will bind to the complementary strand on the chip then it will yield red fluorescence while the other cDNA2 with Cy5 will lead to green color after binding to its complementary strand. However, if the binding of those gene sequences is equal towards the strand present then the orange color which is the intermediate color will produce.

This experiment has been performed by them to understand the properties and the technical set up of DNA microarray.