Before revision: The method was prone to error due to different mRNAs migrated into single bands, differences in less abundant mRNAs getting drowned by more abundant mRNAs, sensitivity to small changes in cell culture conditions, and a tendency to amplify 3 ' fragments rather than full mRNAs, and the necessity to use about 300 primers to catch all the mRNA.
After revision: The method was prone to error due to different mRNAs migrated into single bands, differences in less abundant mRNAs getting drowned by more abundant mRNAs, sensitivity to small changes in cell culture conditions, and a tendency to amplify 3 ′ fragments rather than full mRNAs, and the necessity to use about 300 primers to catch all the mRNA.