Exciting technical developments, especially in the area of molecular diagnostics and pharmacogenomics, hold the promise of a dynamic and evolving field. Molecular diagnostics is being combined with therapeutics and forms an important component of integrated healthcare.
Increasing prevalence of chronic and infectious diseases such as HIV and hepatitis, rising awareness and acceptance of personalized medicine, and companion diagnostics are fueling the growth of molecular diagnostics. Technologies will continue to evolve, allowing faster, more sensitive and less expensive methods for pathogen surveillance and discovery.
Recent times have seen an a wide use of molecular diagnostics tools with increasing applications in blood screening, genetic disorders, and cancer. Molecular biology enzymes, kits, and reagents have found applications in a large number of fields in life science research including diagnostics and drug discovery research. These products are widely used for analysis of cell surface markers, which can act as diagnostics or therapeutic targets. Polymerase chain reactions (PCR) is one of the most widely used analytical and preparative techniques in molecular diagnostics.
The current trends in the field of molecular diagnostics include detection of target genes of interest, profiling mutations associated with disease outcome, and quantification. These trends have been fueled by key developments in technology involving uptake in the diagnostics arena; alternative methods to PCR include SDA, TMA, LCR, NASBA, bDNA; availability of analyte-specific reagents (ASR); trend to real time or kinetic formats; automation; and contamination and inhibitor control.
Automated analyzers. In an effort to deliver better molecular diagnostic products, in vitro diagnostic manufacturers have focused their efforts on simplifying and automating both specimen extraction and nucleic acid detection steps. Newer molecular methods rely on complex in vitro enzymatic reactions performed in central laboratories using extracted and purified nucleic acids from clinical specimens as starting material. Using this technology, test results can be available to the clinician in 2-10 days, depending on the proximity of the testing lab and its frequency of performing such tests.
More recently, manufacturers have begun developing more automated platforms that allow for diagnostic testing but require minimal hands-on time by trained laboratorians. These innovations, in part, have enabled the shift of testing from centralized laboratories to settings closer to the patient, such as hospital labs. The next transformation in molecular testing would be allowing for pathogen detection and identification at point-of-care (POC).
Next-generation sequencing. This emerging technology in the clinical lab is beneficial for improved responsiveness of disease control in healthcare settings and personalization of individual patient therapy. While molecular diagnostics has revolutionized medicine, clinical demands are already stressing the capabilities of established molecular assays, including in the area of antimicrobial resistance and pathogen typing. Sequencing assays offer clinicians profound capabilities in accurate multiplexing with different levels of target definition required by other molecular assays and rich results for clinical and epidemiological use.
Multiplexing. Established molecular assay forms such as real-time PCR (qPCR) have been able to overcome narrow analytical scope through multiplexed testing using panels. Multiplexed panels offer the benefit of positive identification of the infectious agent with shorter turnaround time than repeat single-pathogen tests. Multiplexed molecular assays must often balance panel breadth with accuracy and clarity of results and avoid false-positives which can result from the inclusion of too many targets and sensitivity may be compromised.
Isothermal amplification. Recent technological innovations have enabled nucleic acid testing improvements that make POC molecular diagnostic testing possible. One such innovation has been the advent of isothermal amplification methods which have allowed for rapid detection of DNA/RNA without the requirement for thermal cycling. This technology permits more rapid generation of results, however, it is hampered by its minimal ability to multiplex, long time-to-result, and by the requirement to refrigerate consumables containing enzymes.
Microfluidic sample processing. Droplet microfluidics is a fluidic handling technology that enables precision control over dispensing and subsequent manipulation of droplets in the volume range of microliters to picoliters, on a micro-fabricated device. Miniaturization using microfluidics sample processing has enabled precise control and manipulation of fluids constrained to small (sub-millimeter) scale. This has been used in development of injecting print heads, DNA chips, and lab-on-a-chip technology.
Applications of molecular diagnostics were initially for infections, but are now increasing in the areas of genetic disorders, pre-implantation screening, and cancer. Molecular diagnostics has made possible the diagnosis of the previously undetected viral nucleic acids, early access of data to doctors, a deeper understanding of the disease cause, treatment dose, and success of the treatment depending upon the case. Genetic screening tests, despite some restrictions are a promising area for future expansion of in vitro diagnostics.
Molecular diagnostic technologies are also involved in development of personalized medicine based on pharmacogenetics and pharmacogenomics. There has been a considerable interest in developing rapid diagnostic methods for point-of-care and bio-warfare agents such as anthrax.
In order to successfully capitalize on the opportunities presented by the molecular diagnostics, companies are already exploiting new molecular technologies as corporate strategic assets. Integrating new technology planning with business and corporate strategies will be one of the most challenging tasks for diagnostic companies in the future.