DNA vs. RNA – Which Holds the Key to Early Disease Diagnosis?Posted On: August 16, 2017 | By: Chase Spurlock, PhD
Did you know that genes express themselves in different ways? They do - and they tell a story of an individual’s health and proclivity toward disease.
We grow up learning about DNA in school. Short for deoxyribonucleic acid, DNA is recognized worldwide by its signature double-helix formation and is the poster child of science fairs. And rightly so – DNA contains the instructions an organism needs to develop, live and reproduce.
Changes in DNA have been researched and documented for decades, but there are limitations to how those changes help in the diagnosis of disease. While the changes in DNA have been linked to various autoimmune diseases, scientists have never been able to determine whether or not an autoimmune disease will fully manifest itself using DNA alone. DNA can tell us if we have a propensity to develop a disease – not that we actually will get that disease.
That’s where the lesser-known, but highly essential, RNA steps in. Although RNA is also a nucleic acid, its mission in life is very different than that of its more well-known cousin. RNA, which stands for ribonucleic acid, is present in all living cells. It carries instructions from DNA and canonically controls the synthesis of proteins. In other words, if DNA is considered the blueprint of life, then RNA is the foreman overseeing the work dictated in the blueprint. RNA is tasked with several critical functions in a living organism, from translating genetic information into the molecular machines and structures of the cell that determine everything from hair color and eye color to regulating gene activity as cells develop.
IQuity has been a pioneer in the developing field of RNA research, which is proving to be an exciting specialty focus that will have a profound, and far-reaching, impact on patient diagnosis and treatment, particularly when it comes to autoimmune diseases. RNA diagnostic tools are becoming more widespread, and the implications are incredibly exciting for patients because of the accuracy of these tools and the resulting improvements in the diagnosis process.
RNA and Disease Diagnostics
Did you know that genes express themselves in different ways? They do - and they tell a story of an individual’s health and proclivity toward disease. Gene expression is the degree to which specific genes are turned on or off. Here at IQuity, we are among the first researchers to use machine-learning methods to investigate the link between gene expression and autoimmune diseases.
We used our process IQIsolate to develop algorithms that analyze RNA in a patient’s blood and match gene expression data against that of healthy and sick patients. Our various test panels under IQIsolate determine whether or not the patient’s gene expression pattern is consistent with a specific disease, such as multiple sclerosis (MS) or Crohn’s disease.
For example, our IsolateMS test assesses patients’ RNA levels and distinct gene expression patterns that indicate disease. Our past research results showed that patients with autoimmune disease exhibit distinct RNA expression patterns in their blood that are different from individuals without an autoimmune disease. Thus, our team of researchers concluded that RNA expression patterns could help physicians more quickly diagnose autoimmune conditions. In this case, researchers used machine-learning techniques to create a disease-identifying algorithm.
RNA Provides a More Accurate Tool for Diagnosing Autoimmune Disease
The analysis of RNA expression paints a molecular “selfie,” if you will, of what’s going on in an individual’s cells at a given point in time. This analysis can provide a picture of disease manifestation. At a high level, IQuity’s current RNA testing involves collecting a patient’s blood sample, isolating the RNA and then detecting RNA expression patterns in real time using polymerase chain reaction (PCR). The turning on or off of these expression patterns can serve as an indicator of the presence or absence of disease.
In contrast, DNA tests examine changes in nucleotide sequences to establish a patient’s risk of developing a particular condition. These genotype associations do not always reveal information about disease manifestation. A DNA test, for example, might indicate that a patient is at high risk for an autoimmune disorder, such as rheumatoid arthritis (RA) or MS, but that doesn’t mean the patient will develop the condition. In autoimmunity, DNA measurements alone are an unreliable tool to forecast active disease.
Other types of testing, such as blood tests that detect antibodies, have also been used to detect autoimmune disorders. These testing strategies struggle to capture the entire autoimmune population. Additionally, just because an antibody is not present doesn’t necessarily mean the patient doesn’t have an autoimmune disease. Due to the complex nature of autoimmune diseases, these tests are only incremental steps and put a physician one small step closer to diagnosis, which often leads to additional testing. Analysis of RNA, in our research, provides a robust platform to rule in or rule out disease.
To accurately identify MS, a clinician may need to perform 10 to 15 different tests over what can stretch out to several years from the very first symptoms. If the doctor concludes that a portion of these tests point to the presence of MS, then he or she may be able to make a definitive diagnosis. Unfortunately, it can often take long periods of time for the patient to reach that point.
Revolutionizing the Way Doctors Diagnose Disease
As RNA-based diagnostic testing becomes more widespread, its positive impact on patients, providers and other stakeholders has significant potential. Once widely adopted, this kind of testing could greatly reduce the number of tests and amount of time needed to confirm a diagnosis.
Current autoimmune therapies are effective at slowing disease advancement, but sooner is better when it comes to initiating these therapies. RNA testing can improve outcomes for providers by helping to get patients on the path to suitable treatment earlier. This not only facilitates optimal medication effectiveness but also lessens costs and stress to the patient and improves the management of disease. The future is promising for RNA-based testing, and here at IQuity we are excited to be a pioneer in this field.