What are the differences between whole exome sequencing and RN sequencing?

Basis of differentiation 

Whole exome sequencing

RN sequencing

Definition 

Is a type of sequencing that sequences the DNA coding regions (exons) of the genome

Is a type of sequencing that sequences RNA after conversion to cDNA, focusing on gene expression 

Genomic coverage

Focuses on the exons, which represent about 1-2% of the genome

Covers the transcriptome, including exons, introns, and regions related to gene expression

Data output 

Provides data on DNA mutations and variations 

Provides data on gene expression levels and can detect irregular gene expression patterns 

Primary use

To identify mutations in coding DNA that may lead to genetic disorders or cancer

To study gene expression levels, revealing which genes are active in a tissue or cell type

Expression levels 

Does not measure gene expression levels 

Measures gene expression profiles, reflecting gene activity and providing insight into gene regulation 

Genomic reference 

Requires a known reference genome to target specific exonic regions 

Less dependent on a reference genome – can be used with uncharacterized genomes

Tissue-specific information 

Does not provide tissue specific gene expression data

Provides tissue-specific or cell-specific gene expression data, aiding in understanding disease mechanisms 

Variation detection 

Primarily used for detective genetic variants with a focus on exons 

Can detect variants but with lower confidence due to uneven transcript coverage

Cost and efficiency 

More cost-effective and less time-consuming 

Less cost-effective and more time-consuming as it requires more depth and coverage 

Applications 

Best suited for detecting disease-causing DNA mutations in exons 

Useful for studying gene expression profiles and discovering novel biomarkers