<p><font size="3"><font color="#810081">RNA</font> is less stable in the cell, and also more prone to nuclease attack experimentally. As RNA is generated by transcription from DNA, the information is already present in the cell's DNA. However, it is sometimes desirable to sequence RNA molecules. In particular, in Eukaryotes RNA molecules are not necessarily co-linear with their DNA template, as introns are excised. To sequence RNA, the usual method is first to reverse transcribe convert the sample to generate complimertary DNA fragments, by reverse transcriptase. This can then be sequenced as described above.&nbsp;</font></p>