GeneDx review – Turning data into rare disease diagnosis?


GeneDX Review Summary

GeneDx is a clinical genetic testing company that specializes is rare disease diagnostic. Learn more in our GeneDx review!

Nikki Teran

Ease of use


GeneDx is a clinical genomic testing company that offers FDA approved diagnostics although patients must go through a physician and insurance payments may be complicated.


7 Facts from our GeneDx Review

  1. Location: Gaithersburg, Maryland
  2. Products: Wide variety of clinical genomic tests, medical genetics on rare genetic disorders
  3. Reports: Detailed health reporting for specific genetic conditions
  4. Result delivery: Up to 16 weeks
  5. Privacy: Reports anonymized data to ClinVar
  6. Cost: Highly variable, but can be covered by insurance
  7. Alternatives: Nebula Genomics (Whole Genome Sequencing with weekly updated reports)

This review is written with the intent to be as unbiased as possible. However, it represents the opinion of an individual reviewer and is therefore subjective. Furthermore, at Nebula Genomics we seek to educate the public about the benefits of Whole Genome Sequencing. Information about our Whole Genome Sequencing DNA test is therefore incorporated into the review.

April 13, 2022

Pros and Cons


  • FDA approved diagnostic testing for many rare diseases
  • Contracted with most major insurances


  • No direct patient education
  • Slow turnarounds
  • Insurance complications and unexpected billing

GeneDx Introduction

GeneDx is a clinical genomics company in Gaithersburg, MD, specializing in rare and ultra-rare disease diagnostics. The company is a subsidiary of BioReference Laboratories, Inc., an OPKO Health company. The hybridization-based or next-generation sequencing tests have to be ordered by an MD, a DO, or, in some states, a genetic counselor. These results are returned directly to the clinician.

GeneDx offers its test results as actionable information for patients. According to the site, GeneDx is a world leader in genomics with an acknowledged unparalleled comprehensive GeneDx genetic testing system. But many user reviews complain about the high costs. Many national insurance companies cover its FDA-approved tests, but the out-of-pocket expenses can vary significantly. 

Are you interested in a test that decodes 100% of your DNA instead of only a few genes?

Nebula Genomics offers affordable Whole Genome Sequencing! This full-feature DNA test translates all 20,000 genes and regulatory genomic regions.

In comparison, GeneDx sequences just a few genes at a much higher price. Click here to learn more!

Company Overview

GeneDx is a clinical diagnostic testing company with acknowledged expertise in rare disease diagnostics and clinical laboratories. GeneDx was founded in 2000 as a subsidiary of Bio reference Laboratories by two scientists from the National Institutes of Health (NIH), Drs. Sherri Bale and John Compton. Okpo Health owns the company.

GeneDx believes in responsible testing and diagnostics for improved patient care. The company focuses on delivering testing to patients to diagnose rare and ultra-rare genetic disorders. The company tries to buck the traditional diagnostic advice of, “When you hear hoofbeats, think horses, not zebras” by only focusing on the rare “zebras”.

The company’s first diagnostic test in 2007 used comparative genomic hybridization to look for variations ranging in size from single-gene duplications or deletions to whole chromosome abnormalities. 

In 2008 it started using next-generation sequencing, which gives much better resolution. This allows for detecting changes (variants) in the DNA that only affect a single letter of the DNA alphabet. 

GeneDx began its next-generation sequencing with targeted gene panels for specific rare diseases. As a result, doctors can now verify if one particular broken gene causes a disorder. 

More testing options became available in the early 2010s. In 2012, it began offering whole-exome sequencing, which looks at all genes, but not all DNA. As of 2017, GeneDx also offers whole-genome sequencing. Having both whole exome and genome sequencing allows a doctor to take a more exploratory approach to rare disease diagnostics.

Review of how GeneDx Works

GeneDx works directly with clinicians. A licensed healthcare provider must order the DNA test through a test requisition form, and the results are returned to them.

First, a patient would need to meet with their healthcare provider. If the clinician suspects a specific genetic disorder may be causing the patient’s symptoms, the doctor or genetic counselor can order the testing of a specific gene or set of genes from the GeneDx test menu. If the specific disorder is undetermined, all genes can be sequenced. 

Example of GeneDx genetic testing menu (from the Mayo Clinic)
Example of GeneDx genetic testing menu (from the Mayo Clinic)

Next, the patient then needs to submit a sample. Different tests have different requirements. But GeneDx works with anything they can pull enough DNA from, including blood, cheek swabs, skin biopsies, and even amniocentesis for prenatal screening.

Finally, the clinician will receive a report. This can take up to 16 weeks for full genome sequencing. 

The company also offers rapid exome sequencing through its Xpress product. This test is designed for critically ill patients who present overlapping symptoms. Results are available as soon as 7 days. Notably, it offers up to 58% diagnostic yield for neonates and includes diagnostics for neurodevelopmental disorders.

Review of a GeneDx Sample Report

Below is an example of a positive result. The report indicates panels requested, genes tested, and known disease-causing mutations found.

Annotated testing report from Northwell Health
Annotated testing report from Northwell Health

As you can see, the paper is thorough. It provides insightful information about the genes evaluated and their outcome (positive or negative). Patients also get interesting details, including diagnosis, the clinical significance of mutations found, and recommendations.

Following the patient’s information block is a detailed list of the panels ordered and genes tested. Here, as the clinician was not certain which syndrome matched the patient’s symptoms, multiple panels were ordered. This led to the sequencing of 11 of the roughly 20,000 different genes.

The most important part here is that this mutation is “disease-causing” — based on previous patients GeneDx has examined, it is known that this mutation causes the symptoms the patient has.

The report also includes medical recommendations for the patient and their family members. In this example, the broken gene identified is associated with heart problems, suggesting that the patient should follow up with heart evaluations. Physicians will also consider the patient’s medical records when analyzing the report.

Finally, the report states exactly how the test was performed.

The report can also come back negative, which does not mean there is not a genetic cause to the disorder. GeneDX also clarifies this result on their website.

The results may also reveal “Variants of Uncertain Significance” (VUS) which are variants observed but not considered a positive result — there isn’t enough information to say that that mutation is causing the patient’s disease. 

Keep in mind that the test has limitations. For example, the patient in the above example may have undetected mutations elsewhere. Scientists have not documented every single gene variant responsible for mutations.

Review of GeneDx Clinician Oversight

In a direct-to-consumer DNA test, the consumer requests the test, submits their DNA sample, pays for the analysis, and receives the results. 

For GeneDx, the order is submitted by the clinician and the sample by the patient. The payer is primarily a health insurance company, and the results are sent back to the clinician. 

Only a clinician can order a GeneDx test — either an MD, a DO, or, in some states, a genetic counselor. The tests may only be ordered under established medical guidelines as a diagnostic tool.

The results are only returned to the clinician. GeneDx does employ genetic counselors, but they are GeneDx laboratory genetic counselors that do not work directly with the patient. Instead, their role is to work on the cases and possibly educate an ordering clinician. 

Genetic counseling services are recommended but not provided through GeneDx. You can access genetic counselors through companies such as Genome Medical.

Review of GeneDx Costs

Because the test is a medical diagnostic procedure, price varies by test specifics and insurer.

Financial assistance is offered based on household income and size, including a compassionate care price and payment plans. Details on pricing are not publically available.

Review of GeneDx Privacy

As a medical diagnostics company, GeneDx must comply with the European Union’s General Data Protection Regulation (GDPR) and the United State’s Health Insurance Portability and Accountability Act (HIPAA), and the Health Information Technology Act (HITECH).

GeneDx does report variants it finds to ClinVar, a publicly available database. The data is not personally identifiable but helps other geneticists link together changes in the DNA with their medical outcome in humans. 

In its Notice of Privacy Practices (NOPP), the company specifies that it will not disclose your Protected Health Information (PHI). However, it will disclose it to these entities in the case of treatments, benefits, services, nurses, doctors, and healthcare providers involved in your care. Other cases would be billing and collecting healthcare payments and other applicable instances when required by law.

GeneDx in the News

Since its foundation in 2000, GeneDx has strived to stay in the loop of medical genetics advancements and related expositions. This has established it as a significant player in the global rare disease genetic testing market

In September 2021, the company announced the sequencing of more than 300,000 clinical patient exomes. This is the largest clinical dataset of this kind in the world.  

That same year, in October, GeneDx partnered with Krystal Biotech to offer a product named Krystal Decode DEB. This program has the goal of helping patients with suspected Dystrophic Epidermolysis Bullosa (a rare genetic disease affecting the skin) with early diagnosis and optimal care. Sema4, a health intelligence company, is acquiring GeneDx for approximately $623 million. Sema4 is to acquire GeneDx with a deal to strengthen its artificial intelligence application to healthcare.

Other GeneDx Reviews

GeneDx reviews on Yelp have an average 1-star rating. Reviews complain about unexpected costs, delays in testing, high-pressure sales tactics, and changes in results. 

Google Reviews of GeneDx average to 1.9/5 with similar complaints of insurance issues and complaints from former employees.

The Better Business Bureau gives GeneDx an A+ rating, but note that this does not consider customer reviews. 

Some reviews regarding GeneDx careers suggest that there was previously a toxic working environment in the company. It may be a good place to work fresh out of college, but less fitting for a long term career.

Nebula Genomics

Nebula Genomics offers higher coverage DNA sequencing, works to educate and empower the user, and costs considerably less than diagnostic DNA testing.

Nebula Genomics 30x Whole Genome Sequencing

Whole-exome sequencing covers about 2% of the genome. GeneDx exome sequencing is performed such that at least 95% of the DNA is sequenced at least ten times (called 10x coverage), and at least 98% is sequenced at least once. 

Nebula Genomics goes beyond that — not only is all of the genome sequenced, but each piece is also sequenced 30x coverage on average. Higher sequencing coverage provides better accuracy for finding DNA variants.

Nebula Empowers the User to Learn About Their Own DNA

Nebula wants people to learn about their health, personality, and ancestry. Nebula is committed to explaining cutting edge science simply and accurately. Nebula believes individuals should have the freedom to take charge of their genomic information. This includes using the Nebula Research Library to go through curated research studies.

Nebula also allows users to access all their data. Users can download their raw genomic data and look at it themselves. Nebula even provides information on how to get started and explanations for what it all means.

AncestryDNANebula Genomics
DNA testing methodNext Generation (Single gene, multiple genes, all genes, or whole genome) or hybridization Microarray-based genotypingMicroarray-based genotypingNext generation (Whole Genome Sequencing with 30x coverage)
Able to upload raw DNA dataNoNoNoYes (23andMe and Ancestry)
Downloadable data accessNoYes (23andMe format file)Yes (Ancestry format file)Yes (FASTQ, BAM, and VCF files)
Physician orders needed YesNoNoNo
Informative and educational explanationsNoYes YesYes
Simplified report finding toolsNoYesYesYes (learn more)
CostVariable and often unpredictable$99 or $199$99 or $119$0, $99, $299

Other companies that specialize in rare disease diagnosis include CENTOGENE and Stripe2be. Some biotechnology companies you may be interested in that use genomics to develop novel therapies are Deep Genomics (CNS and metabolic disorders) and Verge Genomics (neurogenerative disorders).

If interested in diagnostic tests, you may also like these other posts.

Diagnostics and disease risks:

  • Ambry Genetics (risks of various disease types)
  • Color (risks of cancer, genetic forms of heart disease, and medication responses)
  • Fulgent Genetics (comprehensive diagnostic company)
  • Oral DNA Labs (specialized diagnostic tool for oral health)
  • Map My Gene (innate talents for children and disease risks)
  • Parsley Health (holistic medicine and health plans)
  • Pathway Genomics (DNA tests for various health aspects, may be used in consultation with medical providers)

Includes carrier status:

  • Integrated Genetics (pre- and post-pregnancy tests)
  • Invitae (diagnostics, proactive health, and reproductive health)
  • Myriad Genetics (diagnostics, reproductive tests, and precision medicine tests)
  • Sema4 (oncology, women’s health, carrier screening, and hereditary cancer)
  • Veritas Genetics (disease risks and carrier screenings)

Mental health:

  • GeneSight (clinical genomic test for psychotropics)
  • Genomind (pharmacogenomic testing for mental health treatment)

Tumor genetics for personalized treatment:

Plus, other DNA tests that provide whole exome sequencing are:

Learn more about whole exome sequencing!

Did you like out GeneDx review? You can find more reviews on our blog and check out our complete guide to the best DNA test kit and other home tests.