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Please help with the following problem.

You perform three microarray experiments in which you measure the mRNA levels in Rb mutant cell line (RB triangle) and in a control cell line (wild-type). The background subtracted. Normalized microarray data for three genes are given below.

Please see the attached MS Word document for the chart.

a. Floor the data to 50. Calculate the average ratio (Rb triangle / wt) of the floored data fro each gene, and write the average ratios below. Which genes are differentially expressed if we use an average ratio threshold of a 2-fold increase or decrease in mRNA levels?

b. Which statistical method would work best in identifying differentially expressed genes in this data set? Write the name of the method below.

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a. Bcl-2: 20/145; 29/157, 38/143,
The average is (20/145+29/157+38/143)/3 = 0.196126
PGK-1: 3714/4508; 3451/4894; 3328/3947
The average is ...

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The following posting helps with problems involving mRNA and microarray experiments. Step by step calculations are given.

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