What is the Difference Between Exome and Transcriptome?

🆚 Go to Comparative Table 🆚

The exome and transcriptome are two distinct sets of genetic information within an organism's genome. The main differences between them are:

  1. Definition: The exome consists of all the exons within the genome, which are the sequences that remain within the mature RNA after introns are removed by RNA splicing. The transcriptome, on the other hand, is a collection of all transcribed RNAs in a cell or tissue, including both non-coding and coding sequences.
  2. Content: The exome is composed of coding sequences and untranslated regions, and it is constant across all cell types. The transcriptome varies between cell types and includes only a portion of the exons that are actually transcribed into mRNA.
  3. Function: The exome is thought to harbor 85% of mutations that have a large effect on disease, while the transcriptome is used to gain insight into cellular differentiation, transcription, phylogenetics, and carcinogenesis processes.
  4. Sequencing: Exome sequencing focuses on the entire set of exons in the genome and requires additional exome-enrichment steps compared to whole-genome sequencing. Transcriptome sequencing, or RNA sequencing, is an alternative approach that bypasses the need for exome enrichment and focuses on the transcribed RNA within a cell type.

In summary, the exome is a collection of all exons in the genome, while the transcriptome is a collection of transcribed RNAs in a cell or tissue. The exome is constant across all cell types, whereas the transcriptome varies depending on the function and structure of the cell. The exome is primarily studied to understand genetic basis of diseases, while the transcriptome is used to gain insights into various cellular processes.

Comparative Table: Exome vs Transcriptome

Here is a table comparing the differences between exome and transcriptome:

Feature Exome Transcriptome
Definition A collection of all exons in a genome A collection of all transcribed RNAs, including both coding and non-coding sequences
Constancy Constant in every cell type Varies according to the function and structure of the cell
Observation Usually observed in sample DNA Usually observed in sample RNA
Composition Composed of coding sequences and untranslated regions Includes exon sequences that are expressed, as well as non-coding RNAs like rRNA, tRNA, and miRNA
Application Efficient in diagnosing genetic disorders Used to study cellular differentiation, transcription, phylogenetics, and carcinogenesis processes
Coverage The human exome is composed of approximately 233,785 exons The size of the human transcriptome varies greatly, but it includes the total number of bases in mRNA, exons, and RefSeq genomes

Exome and transcriptome are two distinct concepts in genetics and genomics. An exome is a collection of all exons in a genome, which are the coding sequences and untranslated regions. Transcriptome, on the other hand, is a collection of all transcribed RNAs, including both coding (primarily mRNA) and non-coding sequences. The exome is constant in every cell type, while the transcriptome varies according to the function and structure of the cell.