Transcriptome

The transcriptome is the set of all RNA molecules (transcripts) in a cell or a population of cells. It includes all of the functional RNA molecules and all other transcripts that may arise by spurious transcription or transcription of non-functional regions such as pseudogenes or virus fragments. A major goal of modern molecular biology is to determine which transcripts are functional and which ones are junk RNA.

The term transcriptome is a portmanteau of the words transcript and genome; it is associated with the process of transcript production during the biological process of transcription. The functional part of the transcriptome is dynamic — it changes with cell type, developmental stage, environment, and stimuli — and therefore represents the active gene expression state rather than the static DNA sequence (genome).

Eukaryotic transcriptomes tend to be more complex than bacterial transcriptomes and the transcriptomes of multicellular eukaryotes are even more complex than those of unicellular eukaryotes.