The proof-of-concept experiment showed data can be encoded in DNA and retrieved using automated systems, a development that may have positive significance for clinical laboratories
It may seem far-fetched, but computer scientists and research groups have worked for years to discover if it is possible to store data on Deoxyribonucleic acid (DNA). Now, Microsoft Research (MR) and the University of Washington (UW) have achieved just that, and the implications of their success could be far-reaching.
Clinical pathologists are increasingly performing genetic DNA sequencing in their medical laboratories to identify biomarkers for disease, help clinicians understand their patients’ risk for a specific disease, and track the progression of a disease. The ability to store data in DNA would take that to another level and could have an impact on diagnostic pathology. Pathologist familiar with DNA sequencing may find a whole new area of medical service open to them.
The MR/UW researchers recently demonstrated a fully automated system that encoded data into DNA and then recovered the information as digital data. “In a simple proof-of-concept test, the team successfully encoded the word ‘hello’ in snippets of fabricated DNA and converted it back to digital data using a fully automated end-to-end system,” Microsoft stated in a news release.
DNA’s Potential Storage Capacity and Why We Need It
Thus far, the challenge of using DNA for data storage has
been that there wasn’t a way to easily code and retrieve the information. That,
however, seems to be changing quite rapidly. Several major companies have
invested heavily in research, with consumer offerings expected soon.
At Microsoft Research, ‘consumer interest’ in genetic testing has driven the research into using DNA for data storage. “As People get better access to their own DNA, why not also give them the ability to read any kind of data written in DNA?” asked Doug Carmean, an Architect at Microsoft, during an interview with Wired.
Scientists are interested in using DNA for data storage because
humanity is creating more data than ever before, and the pace is accelerating.
Currently, most of that data is stored on tape, which is inexpensive, but has
drawbacks. Tape degrades and has to be replaced every 10 years or so. But DNA,
on the other hand, lasts for thousands of years!
“DNA won’t degrade over time like cassette tapes and CDs, and it won’t become obsolete,” Yaniv Erlich, PhD, Chief Science Officer at MyHeritage, an online genealogy platform located in Israel, and Associate Professor, Columbia University, told Science Mag.
Tape also takes up an enormous amount of physical space compared to DNA. One single gram of DNA can hold 215 petabytes (roughly one zettabyte) of data. Wired puts the storage capacity of DNA into perspective: “Imagine formatting every movie ever made into DNA; it would be smaller than the size of a sugar cube. And it would last for 10,000 years.”
Victor Zhirnov, Chief Scientist at Semiconductor Research Corporation says the worries over storage space aren’t simply theoretical. “Today’s technology is already close to the physical limits of scaling,” he told Wired, which stated, “Five years ago humans had produced 4.4 zettabytes of data; that’s set to explode to 160 zettabytes (each year!) by 2025. Current infrastructure can handle only a fraction of the coming data deluge, which is expected to consume all the world’s microchip-grade silicon by 2040.”
MIT Technology Review agrees, stating, “Humanity is creating information at an unprecedented rate—some 16 zettabytes every year. And this rate is increasing. Last year, the research group IDC calculated that we’ll be producing over 160 zettabytes every year by 2025.”
Heavy Investment by Major Players
The whole concept may seem like something out of a science
fiction story, but the fact that businesses are investing real dollars into it
is evidence that DNA for data storage will likely be a reality in the near
future. Currently, there are a couple of barriers, but work is commencing to
overcome them.
First, the cost of synthesizing DNA in a medical laboratory
for the specific purpose of data storage must be cheaper for the solution to
become viable. Second, the sequencing process to read the information must also
become less expensive. And third is the problem of how to extract the data
stored in the DNA.
In a paper published in ASPLOS ‘16, the MR/UW scientists wrote: “Today, neither the performance nor the cost of DNA synthesis and sequencing is viable for data storage purposes. However, they have historically seen exponential improvements. Their cost reductions and throughput improvements have been compared to Moore’s Law in Carlson’s Curves … Important biotechnology applications such as genomics and the development of smart drugs are expected to continue driving these improvements, eventually making data storage a viable application.”
Automation appears to be the final piece of the puzzle. Currently,
too much human labor is necessary for DNA to be used efficiently as data
storage.
It may take some time before DNA becomes a viable medium for
data storage. However, savvy pathology laboratory managers should be aware of,
and possibly prepared for, this coming opportunity.
While it’s unlikely the average consumer will see much
difference in how they save and retrieve data, medical laboratories with the
ability to sequence DNA may find themselves very much in demand because of
their expertise in sequencing DNA and interpreting gene sequences.
Genetic data captured by this new technology could lead to a new understanding of how different types of cells exchange information and would be a boon to anatomic pathology research worldwide
What if it were possible to map the interior of cells and view their genetic sequences using chemicals instead of light? Might that spark an entirely new way of studying human physiology? That’s what researchers at the Massachusetts Institute of Technology (MIT) believe. They have developed a new approach to visualizing cells and tissues that could enable the development of entirely new anatomic pathology tests that target a broad range of cancers and diseases.
Scientists at MIT’s Broad Institute and McGovern Institute for Brain Research developed this new technique, which they call DNA Microscopy. They published their findings in Cell, titled, “DNA Microscopy: Optics-free Spatio-genetic Imaging by a Stand-Alone Chemical Reaction.”
Joshua Weinstein, PhD, a postdoctoral associate at the Broad Institute and first author of the study, said in a news release that DNA microscopy “is an entirely new way of visualizing cells that captures both spatial and genetic information simultaneously from a single specimen. It will allow us to see how genetically unique cells—those comprising the immune system, cancer, or the gut for instance—interact with one another and give rise to complex multicellular life.”
The news release goes on to state that the new technology “shows
how biomolecules such as DNA and RNA are organized in cells and tissues,
revealing spatial and molecular information that is not easily accessible
through other microscopy methods. DNA microscopy also does not require
specialized equipment, enabling large numbers of samples to be processed
simultaneously.”
New Way to Visualize Cells
The MIT researchers saw an opportunity for DNA microscopy to
find genomic-level cell information. They claim that DNA microscopy images
cells from the inside and enables the capture of more data than with
traditional light microscopy. Their new technique is a chemical-encoded
approach to mapping cells that derives critical genetic insights from the
organization of the DNA and RNA in cells and tissue.
And that type of genetic information could lead to new precision medicine treatments for chronic disease. New Atlas notes that “ Speeding the development of immunotherapy treatments by identifying the immune cells best suited to target a particular cancer cell is but one of the many potential application for DNA microscopy.”
In their published study, the scientists note that “Despite enormous progress in molecular profiling of cellular constituents, spatially mapping [cells] remains a disjointed and specialized machinery-intensive process, relying on either light microscopy or direct physical registration. Here, we demonstrate DNA microscopy, a distinct imaging modality for scalable, optics-free mapping of relative biomolecule positions.”
How DNA Microscopy Works
The New York Times (NYT) notes that the advantage of DNA microscopy is “that it combines spatial details with scientists’ growing interest in—and ability to measure—precise genomic sequences, much as Google Street View integrates restaurant names and reviews into outlines of city blocks.”
And Singularity Hub notes that “ DNA microscopy, uses only a pipette and some liquid reagents. Rather than monitoring photons, here the team relies on ‘bar codes’ that chemically tag onto biomolecules. Like cell phone towers, the tags amplify, broadcasting their signals outward. An algorithm can then piece together the captured location data and transform those GPS-like digits into rainbow-colored photos. The results are absolutely breathtaking. Cells shine like stars in a nebula, each pseudo-colored according to their genomic profiles.”
“We’ve used DNA in a way that’s mathematically similar to photons in light microscopy,” Weinstein said in the Broad Institute news release. “This allows us to visualize biology as cells see it and not as the human eye does.”
In their study, researchers used DNA microscopy to tag RNA
molecules and map locations of individual human cancer cells. Their method is
“surprisingly simple” New Atlas reported. Here’s how it’s done,
according to the MIT news release:
Small synthetic DNA tags (dubbed “barcodes” by the MIT team) are added to biological samples;
The “tags” latch onto molecules of genetic material in the cells;
The tags are then replicated through a chemical reaction;
The tags combine and create more unique DNA labels;
The scientists use a DNA sequencer to decode and reconstruct the biomolecules;
A computer algorithm decodes the data and converts it to images displaying the biomolecules’ positions within the cells.
“The first time I saw a DNA microscopy image, it blew me away,” said Aviv Regev, PhD, a biologist at the Broad Institute, a Howard Hughes Medical Institute (HHMI) Investigator, and co-author of the MIT study, in an HHMI news release. “It’s an entirely new category of microscopy. It’s not just a technique; it’s a way of doing things that we haven’t ever considered doing before.”
Precision Medicine Potential
“Every cell has a unique make-up of DNA letters or genotype. By capturing information directly from the molecules being studied, DNA microscopy opens up a new way of connecting genotype to phenotype,” said Feng Zhang, PhD, MIT Neuroscience Professor,
Core Institute Member of the Broad Institute, and
Investigator at the McGovern Institute for Brain Research at MIT, in the HHMI
news release.
In other words, DNA microscopy could someday have applications in precision medicine. The MIT researchers, according to Stat, plan to expand the technology further to include immune cells that target cancer.
The Broad Institute has applied for a patent on DNA
microscopy. Clinical laboratory and anatomic pathology group leaders seeking
novel resources for diagnosis and treatment of cancer may want to follow the MIT
scientists’ progress.
Using animal blood, the researchers hope to improve the accuracy of AI driven diagnostic technology
What does a cheetah, a tortoise, and a Humboldt penguin have
in common? They are zoo animals helping scientists at Saarland University in
Saarbrücken, Germany, find biomarkers that can help computer-assisted diagnoses
of diseases in humans at early stages. And they are not the only animals
lending a paw or claw.
In their initial research, the scientists used blood samples
that had been collected during routine examinations of 21 zoo animals between
2016 and 2018, said a news
release. The team of bioinformatics
and human genetics experts
worked with German zoos Saarbrücken and Neunkircher for the study. The project
progresses, and thus far, they’ve studied the blood of 40 zoo animals, the
release states.
This research work may eventually add useful biomarkers and
assays that clinical
laboratories can use to support physicians as they diagnose patients,
select appropriate therapies, and monitor the progress of their patients. As medical
laboratory scientists know, for many decades, the animal kingdom has been
the source of useful insights and biological materials that have been
incorporated into laboratory assays.
“Measuring the molecular blood profiles of animals has never
been done before this way,” said Andreas
Keller, PhD, Saarland University Bioinformatics Professor and Chair for
Clinical Bioinformatics, in the news release. The Saarland researchers published
their findings in Nucleic Acids
Research, an Oxford
Academic journal.
“Studies on sncRNAs [small non-coding RNAs] are often largely based on homology-based information, relying on genomic sequence similarity and excluding actual expression data. To obtain information on sncRNA expression (including miRNAs, snoRNAs, YRNAs and tRNAs), we performed low-input-volume next-generation sequencing of 500 pg of RNA from 21 animals at two German zoological gardens,” the article states.
Can Animals Improve the Accuracy of AI to Detect Disease
in Humans?
However, the researchers perceived an inability for AI and machine learning to
discern real biomarker patterns from those that just seemed to fit.
“The machine learning methods recognize the typical
patterns, for example for a lung tumor or Alzheimer’s disease. However, it is
difficult for artificial intelligence to learn which biomarker patterns are
real and which only seem to fit the respective clinical picture. This is where
the blood samples of the animals come into play,” Keller states in the news
release.
“If a biomarker is evolutionarily conserved, i.e. also
occurs in other species in similar form and function, it is much more likely
that it is a resilient biomarker,” Keller explained. “The new findings are now
being incorporated into our computer models and will help us to identify the
correct biomarkers even more precisely in the future.”
“Because blood can be obtained in a standardized manner and
miRNA expression patterns are technically very stable, it is easy to accurately
compare expression between different animal species. In particular, dried blood
spots or microsampling devices appear to be well suited as containers for
miRNAs,” the researchers wrote in Nucleic Acids Research.
Animal species that participated in the study include:
Additionally, human volunteers contributed blood specimens
for a total of 19 species studied. The scientists reported success in capturing
data from all of the species. They are integrating the information into their
computer models and have developed a public database of their
findings for future research.
“With our study, we provide a large collection of small RNA
NGS expression data of species that have not been analyzed before in great
detail. We created a comprehensive publicly available online resource for
researchers in the field to facilitate the assessment of evolutionarily
conserved small RNA sequences,” the researchers wrote in their paper.
Clinical Laboratory Research and Zoos: A Future
Partnership?
This novel involvement of zoo animals in research aimed at improving
the ability of AI driven diagnostics to isolate and identify human disease is
notable and worth watching. It is obviously pioneering work and needs much
additional research. At the same time, these findings give evidence that there
is useful information to be extracted from a wide range of unlikely sources—in
this case, zoo animals.
Also, the use of artificial intelligence to search for
useful patterns in the data is a notable part of what these researchers
discovered. It is also notable that this research is focused on sequencing DNA
and RNA of the animals involved with the goal of identifying sequences that are
common across several species, thus demonstrating the common, important
functions they serve.
In coming years, those clinical laboratories doing genetic
testing in support of patient care may be incorporating some of this research
group’s findings into their interpretation of certain gene sequences.
The researchers unveiled a diagnostic device that uses microfluidic technology to identify cell types in blood by their size. The device also “can isolate individual cancer cells from patient blood samples,” according to a news release.
The ability to isolate circulating tumor cells could enable clinical laboratories to perform diagnostic cancer tests on liquid biopsies and blood samples. Dark Daily reported on various studies involving liquid biopsies—an alternative to invasive and costly cancer diagnostic procedures, such as surgery and tissue biopsies—in previous e-briefings.
The UIC and QUT researchers were motivated by the
information-rich nature of circulating tumor cells. They also saw opportunity
for escalated “purity” in results, as compared to past studies.
In the paper, they acknowledged the work of other scientists
who deployed microfluidic technology affinity-based methods to differentiate
tumor cells in blood. Past studies (including previous work by the authors)
also explored tumor cells based on size and difference from white blood cells.
“While many emerging systems have been tested using patient samples, they share a common shortcoming: their purity remains to be significantly improved. High purity is in strong demand for circulating tumor cell enumeration, molecular characterization, and functional assays with less background intervention from white blood cells,” the authors wrote in their paper.
How the Device Works
The scientists say their system leverages “size-dependent
inertial migration” of cells. According to the news release:
Blood passes through “microchannels” formed in
plastic in the device;
“Inertial migration and shear-induced diffusion”
separate cancer cells from blood;
Tiny differences in size determine a cell’s
attraction to a location; and
Cells separate to column locations as the liquid
moves.
In other words, the device works as a filter sorting out, in
blood samples, the circulating tumor cells based on their unique size, New
Atlas explained.
93% of Cancer Cells Recovered by Device
When the researchers tested their new device:
Researchers placed 10 small-cell-lung cancer cells into five-milliliter samples of healthy blood;
The blood was then flowed through the device; and
93% of the cancer cells were recovered.
“A 7.5 milliliter tube of blood, which is typical volume for
a blood draw, might have 10 cancer cells and 35- to 40-billion blood cells. So,
we are really looking for a needle in a haystack,” Papautsky stated in the news
release.
“We report on a novel multi-flow microfluidic system for the
separation of circulating tumor cells with high purity. The microchannel takes
advantage of inertial migration of cells. The lateral migration of cells
strongly depends on cell size in our microchannel, and label-free separation of
circulating tumor cells from white blood cells is thus achieved without
sophisticated sample predation steps and external controls required by
affinity-based and active approaches,” the researchers wrote in their paper.
The researchers plan wider trials and the addition of
biomarkers to enable cancer DNA detection, New Atlas reported, which described
the UIC/QUT study as part of a “new wave of diagnostics.”
With so much focus on liquid biopsy research, it may be
possible for medical laboratories to one day not only diagnose cancer through
blood tests, but also to find the disease earlier and in a more precise way
than with traditional tissue sample analysis.
This research could lead to a useful liquid biopsy test that would be a powerful new tool for clinical laboratories and anatomic pathologists
Cancer researchers have long sought the Holy Grail of
diagnostics—a single biomarker that can quickly detect cancer from blood or
biopsied tissue. Now, researchers in Australia may have found that treasure. And
the preliminary diagnostic test they have developed reportedly can return
results in just 10 minutes with 90% accuracy.
In a news release, University of Queensland researchers discussed identifying a “simple signature” that was common to all forms of cancer, but which would stand out among healthy cells. This development will be of interest to both surgical pathologists and clinical laboratory managers. Many researchers looking for cancer markers in blood are using the term “liquid biopsies” to describe assays they hope to develop which would be less invasive than a tissue biopsy.
“This unique nano-scaled DNA signature appeared in every type of breast cancer we examined, and in other forms of cancer including prostate, colorectal, and lymphoma,” said Abu Sina, PhD, Postdoctoral Research Fellow at the Australian Institute for Bioengineering and Nanotechnology (AIBN), University of Queensland (UQ), in the news release.
“We designed a simple test using gold nanoparticles that
instantly change color to determine if the three-dimensional nanostructures of cancer
DNA are present,’ said Matt
Trau, PhD, Professor of Chemistry at the University of Queensland, and
Deputy Director and Co-Founder of UQ’s AIBN, in the news release.
The team’s test is preliminary, and more research is needed before
it will be ready for Australia’s histopathology laboratories (anatomic
pathology labs in the US). Still, UQ’s research is the latest example of how
increased knowledge of DNA is making it possible for researchers to identify
new biomarkers for cancer and other diseases.
“We certainly don’t know yet whether it’s the holy grail for
all cancer diagnostics, but it looks really interesting as an incredibly simple
universal marker of cancer, and as an accessible and inexpensive technology
that doesn’t require complicated lab-based equipment like DNA sequencing,” Trau
added.
The UQ researchers published their study in the journal Nature Communications. In it, they noted that “Epigenetic reprogramming in cancer genomes creates a distinct methylation landscape encompassing clustered methylation at regulatory regions separated by large intergenic tracks of hypomethylated regions. This methylation landscape that we referred to as ‘Methylscape’ is displayed by most cancer types, thus may serve as a universal cancer biomarker.”
While methyl patterning is not new, the UQ researchers say they were the first to note the effects of methyl pattern in a particular solution—water. With the aid of transmission electron microscopy, the scientists saw DNA fragments in three-dimensional structures in the water. But they did not observe the signature in normal tissues in water.
Their test averaged 90% accuracy during the testing of 200
human cancer samples. Furthermore, the researchers found the DNA structure to
be the same in breast, prostate, and bowel cancers, as well as lymphomas, noted
The Conversation.
“We find that DNA polymeric
behavior is strongly affected by differential patterning of methylcytosine
leading to fundamental differences in DNA solvation and DNA-gold affinity
between cancerous and normal genomes,” the researchers wrote in NatureCommunications.“We exploit
these methylscape differences to develop simple, highly sensitive, and
selective electrochemical or one-step assays for detection of cancer.”
Next Steps for the
“Gold Test”
“This approach represents an exciting step forward in
detecting tumor DNA in blood samples and opens up the possibility of a generalized
blood-based test to detect cancer, Ged Brady, PhD, Cancer Research UK
Manchester Institute, told The
Oxford Scientist. “Further clinical studies are required to evaluate
the full clinic potential of the method.”
Researchers said the next step is a larger clinical study to
explore just how fast cancer can be detected. They expressed interest in
finding different cancers in body fluids and at various stages. Another opportunity
they envision is to use the cancer assay with a mobile device.
DiCarlo told USA Today
that such a mobile test could be helpful to clinicians needing fast answers for
people in rural areas. However, he’s also concerned about false positives. “You
don’t expect all tumors to have the same methylation pattern because there’s so
many different ways that cancer can develop,” he told USA Today. “There
are some pieces that don’t exactly align logically.”
The UQ researchers have produced an intriguing study that differs
from other liquid biopsy papers covered by Dark Daily. While their test may need to be used in combination with other
diagnostic tests—MRI, mammography, etc.—it has the potential to one day be used
by clinical laboratories to quickly reveal diverse types of cancers.