What is the difference between WGS and WES?

The human genome has approximately three billion base pairs, from which about one to five percent are translated into significant proteins. Any mutations that occur in these proteins result in phenotypic consequences. WGS and WES are solutions to find these malfunctions in the genome.

There are significant differences between WGS and WES. These are discussed below.

Whole genome sequencing (WGS)

Whole genome sequencing is used to determine the order of the nucleotides present in the DNA. It can cover the entire human genome, including the mitochondrialMitochondria is the powerhouse of the cell. It is important since it is inherited from the other only and helps in siblings' test., coding, and noncoding parts.

Advantages

WGS has a reliable coverage of the sequences as it has an efficient hybridization capacity.
It allows us to examine the regulatory regions like indelsInserts and deletions in the DNA, structural variations, copy number variations, and single nucleotide variations.
WGS has no reference bias.
This method's library preparation does not require PCR amplification. This reduces any potential GC bias.
WGS has an exceptional coverage uniformity. It enables us to sequence regions of the genome with low sequence complexity.
There is no limit on the read size for WGS. Thus it can read long sequences in one go.

Whole exome sequencing (WES)

Whole exomeThe part of the human genome that contains exons. sequencing is an efficient and comprehensive genetic test that identifies the changes in the DNA rapidly and reliably. It is a genomic technique for sequencing all protein regions of a genome.

Advantages

This sequencing is targeted to exons. Therefore, it reads less than two percent of the genome. This reduces the cost of sequencing the targeted protein region.
Less sequencing region means less storage and analysis costs are required.
The lesser cost allows us to take multiple samples which can be sequenced. This enables us to compare a large population.

Conclusion

In conclusion, a general difference between the two technologies is given below:

Characteristic	WES	WGS
Cost	It's less expensive.	It's more expensive.
Multiple samples	It's easy to sequence multiple samples.	It's multiple sequences require a lot of resources.
Storage capacity	It requries less storage.	It requires more storage.
Reliable coverage	It's less reliable as it leaves out regions.	It's more reliable as hybridization efficiency is better.
Examination of regulatory regions	It covers fewer regions like promoters.	It covers all parts of the genome, including structural variations, indels, exons, and introns.
Reference bias	It can produce false negative SNV calls due to preferentially enriched alleles.	It does not suffer from referential bias.
PCR amplification	It requires PCR amplification due to the bulk input amount needed to capture the DNA.	It does not require PCR amplification during the preparation of the library.
Coverage uniformity	It produces off-target capture effects due to regions of low sequence complexity.	It has a better coverage uniformity.
Read size	It has an input size limitation, smaller reads.	It can take large-sized inputs.

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