Processing Microarray Data: A Larger Sampling

So far we have used only one sample. The expression pattern may be influenced by the cell’s physiological state and many other conditions. To make a general statement about the expression pattern of tumor cells, we need to tease apart meaningful information from many tumor samples.

Even with just five samples and four genes, the pattern gets quite complicated. Can you tell the pattern in the data table? Imagine the difficulty with thousands of genes and hundreds of samples.