You may be familiar with commercial DNA tests that take a small sample of your genetic material and reveal specific genes contributing to predispositions for health care, traits, and ancestry. Above all, these tests can be fun and informative and many people use them to aid medical genetic consultations or discover their ancestors. Ever wonder if you are at a higher risk of celiac disease than the general population? Or if you can find relatives you didn’t know exist through DNA matching? Most commercial tests can help you with these questions. However, did you also know that most tests only look at less than 1% of your entire genome? Genomic research continues to discover associations between the other 99% of your genes and human genetics. For a truly comprehensive view of your genome, you need the full 100%. Whole genome sequencing (WGS) gives you this information.
The table below compares whole genome sequencing and genotyping.
| Genotyping | Whole Genome Sequencing | |
| Purpose | Identify variants already known to be there | Decode all genes as well as all structural and non-coding regions |
| Throughput | Low throughput | High throughput |
| Amount of DNA | <1% of genome (0.5 million positions) | 100% of genome (6 billion positions) |
| Cost | ~ $100 | ~ $299 at Nebula Genomics (usually $1000) |
Do DNA tests sequence my entire DNA?
In most cases, no. Direct to consumer genetic testing companies typically use DNA microarray technology to perform genotyping on your DNA. When a company’s lab receives your sample, it extracts the genetic material and processes the DNA on a genotyping chip. In other words, this technology knows which genetic variants it is looking for and reads hundreds of thousands of specific genes in your genome.
This is why your reports typically focus on very specific traits, like height, rare diseases, or predisposition for health conditions like Alzheimer’s disease.
This is great if you already know what you are looking for or for general inquiries on a variety of traits. But you will always be limited to what the company thinks you should know. And you will never know the results of anything beyond the less than 1% analyzed on that chip.
This is where whole genome sequencing comes as a more complete and comprehensive way to understand your genes.
Advantages of Whole Genome Sequencing
Whole genome sequencing is a next generation sequencing technology that takes a different approach than genotyping methods. Instead of selecting specific variants beforehand, whole genome sequencing decodes nearly 100% of your DNA and can be used to identify previously unknown variants. Genotyping is often thought of as searching for known variants while whole genome sequencing determines the order of your base pairs assuming no prior knowledge.
It reads all 3 billion base pairs to report your entire genetic information. That is to say, the genomics data you receive from whole genome sequencing includes Single Nucleotide Polymorphisms (SNPs), Insertions and Deletions (INDELs), Structural Variations (SVs), Copy Number Variations (CNVs) and Mitochondrial Heteroplasmy (MITO). Genetic research will continue to be ongoing.
As more research comes out on previously undiscovered variants, taking a single DNA sequencing test ensures you have information that can be used for a lifetime. With 30x whole genome sequencing provided by Nebula Genomics, each base pair is read 30 times to ensure accuracy and confidence in the results.
Nebula helps you discover more by continuing to update your reports as new research comes out. With genotyping from other companies, your results are limited to what variants were decided by that company. On the other hand, whole genome sequencing unlocks your complete DNA and points towards new variants as they are discovered.
Whole genome sequencing also makes deep ancestry data analysis easy. Above all, it includes the entire sequence of the mtDNA and Y chromosome (biological males only). By tracing this information consumers can perform genetic genealogy research and trace their ancestors’ migration hundreds and thousands of years.
Whole Genome Sequencing Cost
Overall, the cost of sequencing used to be really expensive. The Human Genome Project, the initiative to sequence a human genome for the first time, took 13 years, dozens of scientists and research institutions, and cost $3 billion. Eventually, biotechnology companies started making the sequencing platform more efficient, bringing the cost of genome sequencing to around $1000.
That’s why previous commercial DNA tests used genotyping. By only selecting a few genetic variations of popular interest, these companies slashed prices.
Additional companies also promoted whole exome sequencing, a sequencing machine between genotyping and whole genome sequencing in terms of price and comprehensiveness. Exome sequencing decodes the protein-coding genes in the genome. This is about 60 million base pairs, or 1% of the human genome. Before whole genome sequencing, these platforms offered affordable means to get more information than genotyping offered at only around $300.
Nebula is the first company able to offer whole genome sequencing, which decodes 100% of your full genome, at an affordable price of $299 or less. By making the extensive results of personal genomics accessible to millions of people around the world, Nebula Genomics is helping public health and giving you back control over your personal genome sequencing data.
March 3, 2022
