Biomarkers Discovery and Complexity of Biological Systems

Biomarkers discovery is one of the most difficult tasks in biology partly due to the level of complexity of biological systems. To start with there are the problems of normal biological variation of 10-40%. This type of variation is impossible to reduce or eliminate from an experiment and thus must be accounted for in the statistical analysis. This variation arises from the differences in individuals resulting 

The exact number of samples that you will need to work with in both the discovery and primary validation phases of the project depends on the techniques that are used and the complexity of the disease and the patient samples that you are working with. 

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