A Statistical Analysis of the SAGE Data
نویسنده
چکیده
Serial Analysis of Gene Expression, or SAGE, is a technology of measuring the expression levels of the mRNA transcripts. The result of a SAGE experiment is reported as a SAGE library, which contains the counts of various short segments (tags) of the cDNA clones. Through a close examination of the SAGE experiment protocol, we derive a new statistical model for the SAGE data, and give new tests for identifying differentially expressed genes and maintenance genes. We find that 2 parameters required by the new model are missing from the current SAGE protocol. Depending on the value of these 2 parameters, the actual variance of the SAGE data could be much larger than what we would expect from the currently used statistical model. We suggest that the current SAGE protocol should be modified to measure these 2 parameters, and give a statistical analysis of the efficiency of the SAGE technology.
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