In the context of the developments in Bioinformatics, the term ‘transcriptome’, sometimes seen in the news, refers to
- (a) a range of enzymes used in genome editing
- (b) the full range of mRNA molecules expressed by an organism ✓ UPSC's answer
- (c) the description of the mechanism of gene expression
- (d) a mechanism of genetic mutations taking place in cells
Why the answer is (b)
• The transcriptome is the complete set of RNA transcripts — chiefly messenger RNA — produced by the genome of a cell or organism at a given time; it shows which genes are switched on and how strongly — option (b).
• Studied by RNA sequencing, it sits between the genome (DNA) and the proteome (proteins).
• Genome-editing enzymes (a) are tools like Cas9; gene-expression mechanism (c) and mutation mechanism (d) are processes, not the transcriptome.
• Hence option (b).
Why the other options are wrong
- (a) a range of enzymes used in genome editing
- Editing enzymes are not the transcriptome.
- (c) the description of the mechanism of gene expression
- The transcriptome is a set of molecules, not a description of a mechanism.
- (d) a mechanism of genetic mutations taking place in cells
- Mutation mechanisms are unrelated.
Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2016, held on 7 August 2016. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.