Normalization
Normalization of transcript quantification data is another possibility to control the quality of the
data. Based on the relationship between the three groups of RNA, pre-existing, newly transcribed and total RNA, a
simple linear regression can be performed for normalization
(Dölken et al., 2008). Since pre-existing and newly transcribed transcript
levels added up should equal total RNA levels, a negative linear correlation should be observed between
the ratios of newly synthesized/total and pre-existing/total RNA.
If only two of the three RNA fractions have been measured, data can be normalized based on the median
half-life.