Pathology Question: Download Pathology PDF
There are about 40 000 human genes and ESTs (expressed sequence tags) available on the Affymetrix Gene Chips for gene expression. Make some reasonable assumptions and estimate, for a normal organ, the number of genes that will appear to be expressed significantly greater than or less than the population norm (95% confidence interval).
Answer:
If we assume that each gene is independent and occurs in a normally distributed population, then one might expect approximately 5% of 40 000 or 2000 genes to appear over expressed or under expressed.