If a child is displaying unusual or rare symptoms and a doctor suspects that they may be genetic in origin, it can begin a cycle of testing that research has indicated could last as long as 77 months or even longer. This is obviously a painstaking process, but doctors are under tremendous pressure to get the diagnosis right. A lot of time is spent analyzing testing options — using the available knowledge of symptoms and previous literature in order to pinpoint the exact genetic test to order.

We must remember that there are about 20,000 genes in the human genome. Of which some 5,000 are recognized to be associated with at least one disease, if not more, and each disease can be associated with dozens of clinical symptoms. Imagine solving a puzzle with 5,000 to 20,000 pieces. But it is even more complicated than that. It becomes a puzzle within the puzzle. The way the genome is set up is that each gene is broken up into different pieces in and of itself. On top of that, there may be important variants within any of those pieces. Genetic testing has traditionally been a lot like fishing in a huge lake.

Historically, genetic testing has been disjointed with so much trial and error. The problem comes with continued negative results. It forces ordering of additional testing in order to identify variants that could be the genesis of the problem. Imagine if an accomplished fisherman was charged every single time he or she threw a lure into a lake. The costs would quickly add up.

Genetic testing becomes a repetitive cycle that causes families emotional and financial stress. The average number of genetic tests a person with a rare disease goes through is four, with some patients having to undergo more than 10. These tests are extremely expensive and some can be quite invasive. Studies have shown the average cost of diagnosis reaching $21,099. All of this is referred to as a “diagnostic odyssey,” where an unfortunate result is delays in diagnoses that can effectively close the treatment window in cases where early treatment improves the prognosis.

Tests developed 10 to 15 years ago are still being run today by laboratories. However, genomic technologies have become more available and accessible recently and it is now possible to look at everything at once using whole genome testing. This new approach to genetic testing is not so much like fishing in a huge lake anymore. This new approach provides the most useful diagnostic data with a single test that is easier on patients and families and provides the shortest time to a diagnosis and the best chance at implementing treatments and eliminating the diagnostic odyssey.

More studies are showing the clinical utility of sequencing the whole genome as a cost-effective solution, saving as much as seven times the average cost of standard care. Clinicians ordering a single whole genome sequencing test right off the bat provide patients a better chance of not having to endure the long, cumbersome, and costly process of multiple single-gene tests. With whole genome sequencing , a patient needs only one sample and one turnaround time for the greatest chance to arrive at the correct diagnosis.

Just as important, with whole genome sequencing, negative test results do not require once again starting from scratch. If a new gene associated with the patient's suspected disease is reported the next day, and that patient had a variant in that gene, a clinician can make the connection through data reanalysis rather than by bringing the patient back in for a new sample.

Specifically, advances in whole genome sequencing bypass the mechanical step of isolating genes first. Analysis of the large amounts of data generated is made possible by the use of sophisticated algorithms applied via software that identifies variants that labs do not typically see when one starts by isolating genes. Variants can then be ranked by looking at genes that most closely match the patient's clinical symptoms or known inheritance patterns. For the first time, a broad set of variants can be looked at through two lenses: one that shows the severity of the identified changes, and the other that matches the changes with the clinical symptoms of the patient.

These are the ways whole genome testing is revolutionizing the entire genetic testing industry by providing a comprehensive analysis with the shortest time to diagnosis and thus saving patients a lot of money and the emotional toll that comes with a long wait for a diagnosis.

Christine Stanley, PhD, is the Chief Director of Clinical Genomics for Variantyx