Microarray technologies have the potential to add significant value to the field of clinical diagnostics. This powerful technology is high-throughput and sensitive, allowing for the rapid screening of many genetic markers in parallel.

In this blog post, we explore how the diagnostic information provided by this impressive tool could empower clinicians to make confident decisions on patient care and lead to bespoke, personalised treatments across different medical specialties.

What is a microarray?

Microarrays are tools onto which thousands of DNA or RNA probes are immobilised in a grid. They are used to measure the expression of many genes simultaneously.

Probes that specifically bind to targets within these genes of interest are printed in small spots onto solid surfaces, commonly made of glass or silicon. Typically, DNA is amplified and labelled, then the labelled product is passed over the printed probe spots.

If the probes and the amplified target match, they will adhere to one another in a process known as hybridisation. Following washing of the array, any hybridised targets/probes will appear as bright spots, indicating that a sample is positive for that specific gene (Figure 1).

Thousands of spots can be printed on a single microarray slide; therefore, thousands of gene targets can be screened in parallel.

Microarrays applied to infectious diseases

Microarray technologies can be used in almost any medical field, including detection of infectious diseases. Patient samples can be rapidly and precisely screened for hundreds of different pathogens at once. This leads to prompt diagnosis, facilitating timely and appropriate patient management.

Rapid diagnosis also enables healthcare professionals to employ appropriate infection prevention measures, as well as allowing for the implementation of effective public health interventions to contain any potential outbreaks.

Enhanced pathogen detection with microarrays

Microarray technologies offer heightened sensitivity in detecting pathogens, especially polymicrobial infections or those that are challenging to culture. By swiftly and precisely screening patient samples for hundreds of pathogens simultaneously, microarrays enable early diagnosis; which is vital for timely patient management.

This heightened sensitivity not only aids in identifying elusive pathogens, but also facilitates the prompt implementation of infection prevention measures and public health interventions to contain potential outbreaks effectively.

Microarrays and antimicrobial resistance

In addition to their use in screening for infectious diseases, microarrays could also be used in the fight against antimicrobial resistance (AMR). AMR describes the situation when bacteria (and other microbes) become resistant to the drugs that previously would have killed them.

AMR is a global health concern and was responsible for an estimated 1.27 million deaths worldwide in 2019. It is becoming increasingly difficult to treat some infections, particularly those caused by bacteria, leading to a poorer outcome for patients.

Microarrays offer a diagnostic advantage over traditional molecular methods in that they allow for the screening of multiple markers for AMR, alongside pathogen screening, allowing for both rapid diagnosis and informed treatment options.

Other diagnostic applications for microarrays

Cancer diagnostics

Microarrays can be used to profile tumour genomes, detecting specific mutations, chromosomal alterations, and specific gene expression patterns in cancer cells.

This information can be used to facilitate targeted therapies and predict chemosensitivity, allowing for the development of a more personalised treatment strategy.

Prenatal screening

Microarrays help identify chromosomal issues in newborns. Traditional karyotyping checks chromosomes under a microscope to look for visual defects, but this is only sensitive enough to detect larger genetic faults. Chromosomal microarray analysis provides better resolution and can spot smaller issues at once. This means early detection, comprehensive analysis, and more informed decisions for parents and healthcare providers.

Pharmacogenomics

Microarrays can be used to predict how an individual will respond to certain drugs based on their genetics, a topic known as pharmacogenomics.

Knowledge of links between genetic signatures and an individual’s response to a drug can be used to predict drug efficacy, prevent adverse reactions, optimise dosing regimens, and deliver optimised treatments quickly.

Microarrays: challenges to overcome

Despite the multitude of applications of microarray technologies as a diagnostic tool, certain factors need to be considered before their introduction into a diagnostic pathway, such as:

• Development resources: a vast amount of sequencing information is required to develop a microarray into a diagnostic test.
• Complexity of the analysis: accurate and reliable analysis and interpretation of the large amount of data generated by an array can be time-consuming.
• Nature of the result: depending on microarray design, results are not always quantitative, and may not be predictive of relative concentration. For instance, the microarray can determine that a certain virus is present, but not the viral load/infectiousness of the patient.

Microarrays: what’s next?

Improvements in accessibility to bioinformatics resources and tools, and leaps in the processing power of computers, are increasing the speed at which we analyse and interpret large amounts of data.

The combination of microarrays and artificial intelligence (AI) is transforming healthcare; AI algorithms can rapidly analyse microarray data, identifying genetic patterns for disease diagnosis and treatment prediction.

This integration enables personalised interventions based on individual genetic profiles and clinical data, improving diagnostic precision and guiding treatment strategies for better patient outcomes.

Continued development of microarray technology and standardisation of protocols is crucial if we are to ensure reliability and reproducibility of microarrays, allowing for further integration into routine clinical practice and making personalised medicine available to all.

From infectious diseases to cancer diagnostics, microarrays empower informed decision-making and early detection. Looking to the future, the integration of microarrays with AI technology promises enhanced disease prediction and treatment.

Future of molecular diagnostics with QuantuMDx

QuantuMDx is passionate about transforming molecular diagnostics through innovative PCR and microarray technology solutions. Explore how our products and solutions are shaping the future of multiplex diagnostics.

Join us in innovating the future of healthcare with microarrays, ensuring reliable, accessible and effective healthcare for all patients. If you have a hi-plex, molecular assay which could benefit from automation at the point of need, we invite you to get in touch with the QuantuMDx team.