Clinical laboratory managers should note that this company’s new diagnostic offering involving screening embryos for specific genetic conditions is not without controversy
Is the world ready for whole genome sequencing (WGS) of preimplantation embryos to help couples undergoing in vitro fertilization (IVF) treatments know if their embryos have potential genetic health problems? Orchid Health, a clinical preimplantation genetic testing (PGT) laboratory that conducts genetic screening in San Francisco, believes the answer is yes! But the cost is high, and the process is not without controversy.
According to an article in Science, Orchid’s service—a sequencings of the whole human genome of preimplantation embryos at $2,500 per embryo tested—“will look not just for single-gene mutations that cause disorders such as cystic fibrosis, but also more extensively for medleys of common and rare gene variants known to predispose people to neurodevelopmental disorders, severe obesity, and certain psychiatric conditions such as schizophrenia.”
However, Science also noted that some genomics researchers “claim the company inappropriately uses their data to generate some of its risk estimates,” adding that the “Psychiatric Genomics Consortium (PGC), an international group of more than 800 researchers working to decode the genetic and molecular underpinnings of mental health conditions, says Orchid’s new test relies on data [PGC] produced over the past decade, and that the company has violated restrictions against the data’s use for embryo screening.”
There are some who assert that a whole genome sequence of an embryo—given today’s state of genetic technology and knowledge—could generate information that cannot be interpreted accurately in ways that help parents and doctors make informed prenatal testing decisions. At the same time, criticisms expressed by the PGC raise reasonable points.
Perhaps this is a sign of the times. Orchid Health is the latest genetic testing company that is looking to get ahead of genetic testing competitors with its diagnostics offerings. Meanwhile, knowledgeable and credible experts question the appropriateness of this testing, given the genetic knowledge that exists today.
“This is a major advance in the amount of information parents can have,” Orchid’s founder and CEO Noor Siddiqui (above) told CNBC. “The way that you can use that information is really up to you, but it gives a lot more control and confidence into a process that, for all of history, has just been totally left to chance.” Should Orchid Health’s analysis prove useful, pediatricians could order further clinical laboratory prenatal testing to confirm and diagnose potential genetic diseases for parents. (Photo copyright: General Assembly.)
Orchid Receives World-class Support
Regardless of the pushback from some genetic researchers, Orchid has attracted several world-class geneticists and genetics investors to its board of advisors. They include:
Jacques Cohen, PhD, embryologist, co-founder and former director for genetics laboratory Reprogenetics LLC (now CooperGenomics).
Anne Wojcicki, co-founder and CEO of direct-to-consumer genetic testing company 23andMe.
and others.
The WGS test, according to Orchid, detects genetic errors in embryos that are linked to severe illnesses before a pregnancy even begins. And by sequencing 99% of an embryo’s DNA, the test can spot potential health risks that could affect a future baby.
According to its website, the PGT lab company uses the WGS data to identify both monogenic (single-gene) and polygenic (multiple-gene) diseases, including:
Orchid is not without its critics. Knowledgeable, credible experts have questioned the appropriateness of this type of genetic testing. They fear it could become a modern-day form of eugenics.
Andrew McQuillin, PhD, Professor of Molecular Psychiatry at University College London, has concerns about Orchid’s preimplantation genetic testing. He maintains that it is difficult to control how such data is used, and that even the most accurate sequencing techniques do not predict disease risk very well.
“[Polygenic risk scores are] useful in the research context, but at the individual level, they’re not actually terribly useful to predict who’s going to develop schizophrenia or not,” McQuillin told Science. “We can come up with guidance on how these things should be used. The difficulty is that official guidance like that doesn’t feature anywhere in the marketing from these companies.”
McQuillin also stated that researchers must have an extensive discussion regarding the implications of this type of embryo screening.
“We need to take a look at whether this is really something we should be doing. It’s the type of thing that, if it becomes widespread, in 40 years’ time, we will ask, ‘What on Earth have we done?’” McQuillin emphasized.
Redefining Reproduction
It takes about three weeks for couples to receive their report back from Orchid after completing the whole genome sequence of a preimplantation embryo. A board-certified genetic counselor then consults with the parents to help them understand the results.
Founder and CEO Noor Siddiqui hopes Orchid will be able to scale up its operations and introduce more automation to the testing process to the cost per embryo.
“We want to make this something that’s accessible to everyone,” she told CNBC.
“I think this has the potential to totally redefine reproduction,” she added. “I just think that’s really exciting to be able to make people more confident about one of the most important decisions of their life, and to give them a little bit more control.”
Clinical laboratories have long been involved in prenatal screening to gain insight into risk levels associated with certain genetic disorders. Even some of that testing comes with controversy and ambiguous findings. Whether Orchid Health’s PGT process delivers accurate, reliable diagnostic insights regarding preimplantation embryos remains to be seen.
Three innovative technologies utilizing CRISPR-Cas13, Cas12a, and Cas9 demonstrate how CRISPR might be used for more than gene editing, while highlighting potential to develop new diagnostics for both the medical laboratory and point-of-care (POC) testing markets
CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) is in the news again! The remarkable genetic-editing technology is at the core of several important developments in clinical laboratory and anatomic pathology diagnostics, which Dark Daily has covered in detail for years.
Now, scientists at three universities are investigating ways to expand CRISPR’s use. They are using CRISPR to develop new diagnostic tests, or to enhance the sensitivity of existing DNA tests.
One such advancement improves the sensitivity of SHERLOCK (Specific High Sensitivity Reporter unLOCKing), a CRISPR-based diagnostic tool developed by a team at MIT. The new development harnesses the DNA slicing traits of CRISPR to adapt it as a multifunctional tool capable of acting as a biosensor. This has resulted in a paper-strip test, much like a pregnancy test, that can that can “display test results for a single genetic signature,” according to MIT News.
Such a medical laboratory test would be highly useful during pandemics and in rural environments that lack critical resources, such as electricity and clean water.
One Hundred Times More Sensitive Medical Laboratory Tests!
MIT News highlighted the high specificity and ease-of-use of their system in detecting Zika and Dengue viruses simultaneously. However, researchers stated that the system can target any genetic sequence. “With the original SHERLOCK, we were detecting a single molecule in a microliter, but now we can achieve 100-fold greater sensitivity … That’s especially important for applications like detecting cell-free tumor DNA in blood samples, where the concentration of your target might be extremely low,” noted Abudayyeh.
“The [CRISPR] technology demonstrates potential for many healthcare applications, including diagnosing infections in patients and detecting mutations that confer drug resistance or cause cancer,” stated senior authorFeng Zhang, PhD. Zhang, shown above in the MIT lab named after him, is a Core Institute Member of the Broad Institute, Associate Professor in the departments of Brain and Cognitive Sciences and Biological Engineering at MIT, and a pioneer in the development of CRISPR gene-editing tools. (Photo copyright: MIT.)
Creating a Cellular “Black Box” using CRISPR
Another unique use of CRISPR technology involved researchers David Liu, PhD, and Weixin Tang, PhD, of Harvard University and Howard Hughes Medical Institute (HHMI). Working in the Feng Zhang laboratory at the Broad Institute, they developed a sort of “data recorder” that records events as CRISPR-Cas9 is used to remove portions of a cell’s DNA.
They published the results of their development of CRISPR-mediated analog multi-event recording apparatus (CAMERA) systems, in Science. The story was also covered by STAT.
“The order of stimuli can be recorded through an overlapping guide RNA design and memories can be erased and re-recorded over multiple cycles,” the researchers noted. “CAMERA systems serve as ‘cell data recorders’ that write a history of endogenous or exogenous signaling events into permanent DNA sequence modifications in living cells.”
This creates a system much like the “black box” recorders in aircraft. However, using Cas9, data is recorded at the cellular level. “There are a lot of questions in cell biology where you’d like to know a cell’s history,” Liu told STAT.
While researchers acknowledge that any medical applications are in the far future, the technology holds the potential to capture and replay activity on the cellular level—a potentially powerful tool for oncologists, pathologists, and other medical specialists.
Using CRISPR to Detect Viruses and Infectious Diseases
Another recently developed technology—DNA Endonuclease Targeted CRISPR Trans Reporter (DETECTR)—shows even greater promise for utility to anatomic pathology groups and clinical laboratories.
Also recently debuted in Science, the DETECTR system is a product of Jennifer Doudna, PhD, and a team of researchers at the University of California Berkeley and HHMI. It uses CRISPR-Cas12a’s indiscriminate single-stranded DNA cleaving as a biosensor to detect different human papillomaviruses (HPVs). Once detected, it signals to indicate the presence of HPV in human cells.
Despite the current focus on HPVs, the researchers told Gizmodo they believe the same methods could identify other viral or bacterial infections, detect cancer biomarkers, and uncover chromosomal abnormalities.
Future Impact on Clinical Laboratories of CRISPR-based Diagnostics
Each of these new methods highlights the abilities of CRISPR both as a data generation tool and a biosensor. While still in the research phases, they offer yet another possibility of improving efficiency, targeting specific diseases and pathogens, and creating new assays and diagnostics to expand medical laboratory testing menus and power the precision medicine treatments of the future.
As CRISPR-based diagnostics mature, medical laboratory directors might find that new capabilities and assays featuring these technologies offer new avenues for remaining competitive and maintaining margins.
However, as SHERLOCK demonstrates, it also highlights the push for tests that produce results with high-specificity, but which do not require specialized medical laboratory training and expensive hardware to read. Similar approaches could power the next generation of POC tests, which certainly would affect the volume, and therefore the revenue, of independent clinical laboratories and hospital/health system core laboratories.
A growing number of media stories claim medical lab companies that develop genetic screening assays oversell the accuracy of such tests and fail to educate parents and doctors about the risks of false positives and false negatives
In response to growing concerns by consumers about the accuracy of some proprietary genetic screening assays, several media outlets have begun reporting on this sector of the clinical laboratory industry.
What gives these news stories emotional punch is the fact that patients use these proprietary medical laboratory tests to make decisions that can be life-changing. In its story about these tests, the Boston Sunday Globe used the headline “Oversold prenatal tests spur some to choose abortions.” (more…)
Prenatal genome sequencing raises ethical issues for gene sequencing labs and clinical labs, since a baby’s genetic information may present lifelong consequences for that individual
Notably, it was geneticist and graduate student Razib Khan of the UC Davis School of Veterinary Medicine who sequenced his unborn son’s genome during the third trimester of pregnancy using a sample of the fetus’ placenta. This is the first healthy person born in the United States with his entire genetic makeup deciphered prior to birth, noted a recent story published by the MIT Technology Review. (more…)
