When the sequencing of the human genome was completed over a decade ago, there was enormous hope that the equally enormous potential encoded in those 3 billion base pairs of DNA would unlock the mystery of human disease if not of our very existence itself. However, I don't think it's too much of an exaggeration to say that the code from which we derive remains pretty much that - a code - and that there is much that still needs decrypting regarding tthe double helix and this mortal coil.
One area where we have made significant progress thanks to genome sequencing is in medical diagnostics and predicting the likelihood of not only succumbing to a particular disease but also of how a patient may respond to standard-of-care treatment. As the public becomes more and more educated about the value of the information intertwined in their double helix, personalized medicine became the goal and the race was on to get to the magical "thousand dollar genome", thereby making it much more of a test reachable for "everyone".
We are currently in the era of thousand dollar genome sequencing and personalized medicine is becoming more of an everyday term, but to routinely use DNA sequence analysis as a tool in contemporary medicine there remains a need for faster, cheaper high throughput DNA sequencing. A new development referred to as "atomic chicken wire" may represent the future in this area, with one atom layers of hexagonally arranged carbon (graphene) being the key - the authors of a recent paper in Nature reporting that graphene can measurably detect adenine, guanine, cytosine and thymine - the four nucleobases making up our DNA.
The ability of each base to impact the electronic structure of the graphene sheet allows that impact to be measured electrically, potentially permitting major improvements in speed, throughput and accuracy of DNA sequencing. The idea is that a single DNA molecule passes through a nanopore in the graphene sheet "like a string of beads passing through chicken wire" and the graphene sensor reads the sequence in high throughput fashion in real time. It's a potentially explosive technology and one can imagine bulk graphene sensors simultaneously reading multiple molecules of DNA with individual costs being reduced dramatically.
Another diagnostic area where nanoparticles are making a big splash is prostate cancer. Never mind the thousand dollar genome, researchers at the University of Central Florida (UCF) have developed a $1 blood test using gold nanoparticles that outperforms the current PSA screen for prostate cancer. This is eztremely exciting given that the earlier we detect basically any cancer, the better the chance that we can resolve it before it becomes unmanageable.
The simple test developed by UCF scientist Qun Huo makes significantly earlier detection possible, and that's massive for one of the deadliest cancers in men. Huo's test takes advantage of the unique ability of gold particles to absorb and scatter light, and is focused on the body's immune response to cancer whereby certain biomarkers (antibodies) that are upregulated adhere to the gold nanoparticle surface, changing their size and light scattering properties.
Huo's team at UCF's NanoScience Technology Center developed a technique known as nanoparticle-enabled dynamic light scattering assay (NanoDLSay) to measure the size of the particles by analyzing the light they scatter - that size reveals whether a patient has prostate cancer and additionally indicates how advanced it may be. Although we normally associate gold with great expense, in this case the nanopartciles mean a nanocost and this could make such a test totally routine from a finger prick of blood in the doctor's office.
Prostate cancer is the #2 cause of deaths due to cancer in men, with close to a quarter of a million new diagnoses and 28,000 deaths each year. To date, the PSA test is the most routine screening tool available, but it produces many false positive results -- resulting in painful biopsies and elaborate treatments -- and detractors have likened it to nothing more than a coin toss in terms of reliability. The need is real and Huo's test could be a total game changer in men's health and medical treatment.
Pilot studies on Huo's test have shown that it determines with 90-95% confidence that the result is not a false positive, while in terms of false negatives, the test is less reliable (50% confidence); however this is still significantly higher than the PSA test's 20% confidence in false negatives, and Huo is working to improve this number. The data from this pilot study were published recently in ACS Applied Materials & Interfaces and Huo is also scheduled to present her findings in June at the TechConnect World Innovation Summit & Expo in Washington, D.C.
She hopes to complete major clinical trials quickly and get the test in doctor's hands in two or three years, while also researching how the technique could be used for various other cancers, stating that she could be onto a "potentially universal screening test for cancer". On the back of her discoveries, Huo has co-founded Nano Discovery Inc., a UCF startup which will commercialize the new diagnostic test once it obtains marketing approval.
This cheap test using nanoparticular gold could be worth way more than its weight in gold, and the only aspect of it that will remain "nano" will be the size of the particles themselves! At AmorChem, we have a keen eye on the nanotechnology space and in fact we recently invested in a nanoparticle technology discovered at the University of Waterloo. The field is forging ahead and it's only a matter of time until approaching medicine from the most minute viewpoint will pay off enormously in terms of the bigger picture.
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