What is the GA-Map® Dysbiosis Test Lx?
What are the indications for use?
With trillions of bacteria residing in the gut, this dynamic community is sensitive to many factors including host lifestyle, diet and immunity, which influence the diversity and abundance of different bacteria colonising the gut. As a result, dysbiosis (i.e. a deviation from a normal and healthy reference microbiome) is common.
In the field of Gastroenterology and digestive health there are many indications for gut microbiota testing. Testing your patients stool samples using GA-Map® identifies microbiota dysbiosis which supports the diagnosis, treatment and monitoring of numerous digestive diseases.
For those difficult-to-treat conditions such as Irritable Bowel Syndrome (IBS), Inflammatory Bowel Disease (IBD), changes in bowel habits, functional gastrointestinal disorders, diarrhoea, GA-Map® dysbiosis test Lx may help unveil the underlying cause of symptoms and help direct patient-specific treatment.
New indications for microbiota testing are being explored all the time thanks to a vibrant community with great interest in the value of microbiota research. As a result, evidence is emerging at an incredible pace. For example, in the field of gastroenterology alone dysbiosis has been implicated in non-alcoholic fatty liver disease (NAFLD), diabetes, and obesity. Recently it was proposed that Gut microbiota analysis be used to assess the efficacy of faecal microbiota transplants (FMT) in the treatment of Clostridium difficile infection.
In IBS, GA-Map® Dysbiosis Test Lx has demonstrated how gut microbiota bacterial profiles can be used to predict the efficacy of dietary intervention using traditional IBS and Low-FODMAP diets (Bennet et al). Such findings have led to the exploration of how gut microbiota can predict the outcome of treatments for various gastrointestinal diseases.
Determine if a patient is non-dysbiotic or dysbiotic (and the degree of dysbiosis) compared to a normobiotic reference range given in the GA-map® Dysbiosis Test Lx.
In patients where organic disorders have been ruled out, GA-map® can identify dysbiosis in:
symptomatic non-IBD patients (patients with negative colonoscopy results)
Establish microbiota profiles
GA-map® provides a convenient means of establishing an individual's gut microbiota profile, reporting bacteria levels compared to a normobiotic reference in:
Symptomatic non-IBD patients (patients with negative colonoscopy results)
Patients with functional gastrointestinal disorders
Monitoring response to therapeutic, dietary and lifestyle interventions helps manage resources and follow-up in:
IBS (e.g. Low FODMAP diet)
IBD (e.g. anti-TNFa therapy)
Clostridium difficile (e.g. FMT intervention)
The GA-Map® Dysbiosis Test Lx is a gut microbiota DNA analysis tool to identify and characterise dysbiosis.
It is used together with other clinical information to support the diagnosis and management of patients with IBS and IBD. Specifically, GA-Map® is classified as an in-vitro diagnostic test for the semi-quantitative measurement of bacterial 16S rRNA in stools from patients with IBS, IBD, and symptomatic non-IBD. It can help in many ways including diagnosis, monitoring and evaluating the response to treatment in a number of digestive diseases.
The technology exploits single nucleotide differences in the 16S rRNA gene to measure the abundance of species and groups of bacteria in a faecal sample. All pre-processing of the data is carried out by the sophisticated GA-Map® Analyzer software, and so no bioinformatician resources are needed to analyse results.
Reports containing the microbiota profiles are automatically generated which include information on the dysbiosis index - a measure of how the individual's bacteria profile differs from a reference population. By combining the speed, precision and robustness of RT-PCR applications with the comprehensiveness of next generation sequencing, the GA-Map® technology dramatically reduces the time from analysis to publication.
Modifying the gut microbiota
The factors that influence gut microbiota and microbial diversity are well documented. Genetics, age, diet, physical activity, mood/stress, medications, age, inflammation, infection all have an affect on the microbial composition in the gut.
The microbiota, and subsequently an indivudal's health, can be modified by manipulating certain factors that influence the microbiota. Current approaches to modulating the microbiota to derive clinical benefit include:
Diet low in Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAP)
Fecal microbiota transplantation (FMT)
Synbiotics (combination of pre- and probiotics)
Rifaximin (an antibiotic)
GA-Map® technology - how it works
The GA-Map dysbiosis test is based on the detection of bacterial DNA using cutting edge techniques that:
Significantly increase the number of bacteria species that can be found in a stool sample
Dramatically reduce detection time compared to conventional techniques
Simplify sample handling – no need for culture or live bacteria
Simplify data analysis of the microbes detected
The Bacterial 16S rRNA gene
The patented GA-map® technology utilises constant and variable DNA sequences within the 16S rRNA gene of the bacteria to identify and characterise the different bacteria. The test enables simultaneous analysis of a large number of gene fragments in one reaction.
The GA-map® Dysbiosis Test is based on advanced DNA profiling techniques to target variable regions (V3 to V9) of amplified bacterial 16S rRNA genes in order to identify and characterise bacteria that make up the gut microbiota.
Genomic DNA derived from a single stool sample is the primary sample. The gene targets are identified using a highly specific set of 48 probes in a molecular multiplex assay that utilises the patented Single Nucleotide Primer Extension (SNuPE) technology. A unique algorithm is then employed to reduce all the data generated by the detection of the SnuPE products to determine the dysbiosis level in the sample. The algorithm is incorporated in the GA-map® Dysbiosis Analyzer software that accompanies the test and so data reduction is made simple.
GA-map® Dysbiosis Test Lx comprises eight steps:
Fecal sample collection
Genomic DNA extraction
Amplification of 16S rRNA gene
DNA Quality Control (QC)
Preparation of test report
How does GA-Map compare to Next Generation Sequencing (NGS)?
The main benefit of using GA-Map technology over other applications (e.g. Next Generation Sequencing) comes from the standardisation and consistency of results given which in turn are indexed against a normal control population, giving reassurance to the clinician that the Dysbiotic Index is reliable. As a result, the GA-Map® Dysbiosis Test Lx is CE marked for clinical use too with simple data reduction for easy implementation.
The results are presented in an easy to read format and include a comprehensive profile of the patient's gut microbiota with a Dysbiosis level between 1 and 5. The Dysbiosis Index is based on the relative abundance of individual bacteria compared to a healthy (control) population.
Next Generation Sequencing (NGS)
Normal control population included
Automated report generation
All bacteria present, Relative abundance, Diversity index
Pre-defined bacteria targets, Relative Abundance, Dysbiosis Index
6 - 14 days
Illumina, Ion Torrent
16s rRNA span
v3 and / or v4 region
v3 - v9
PCR primer pair coverage
200-300 base pairs
1180 base pairs tested against 436 target species
Routine Clinical or Research
* Dysbiosis Index.
Faecal microbiota analyses requires expert input to get high quality and reproducible data. BIOHIT HealthCare makes accessing a microbiota analytical service simple, but if you prefer to set up the technology to perform your own analyses our experts will bring the technology to you with all the support you need to establish a successful service.
BIOHIT HealthCare can help with research applications that require professional microbiota analysis delivered by experts in the field. We collaborate with researchers to build the evidence needed to bring benefits to patients from diagnostic and therapeutic interventions that involve analysis and manipulation of the microbiome.
What kind of treatment can be used to alter the microbiota?
Pro- and prebiotics, different diets (e.g. low FODMAP diet) and antibiotics such as Rifaximin, as well as faecal microbiota transplantation (FMT), can all change the microbiota composition.
How can a result be non-dysbiotic according to the Dysbiosis index, when several of the bacteria are deviating?
Some deviation from normal is expected in some of the bacteria. In the algorithm used to calculate the Dysbiosis index, bacteria are weighted differently. The weighting of the particular bacteria contribute to the final Dysbiosis Index.
Can the patient be tested again later and test result compared to present results?
Yes, the GA-map® Dysbiosis Test Lx is developed to give consistent results over time. Patient results can therefore be monitored during treatment or in follow-up post intervention to observe changes in their microbiota.
The single bacteria and bacteria groups were selected from the literature showing correlation in IBS and IBD patients. The bacteria markers used in the test is a selection from a large number of markers tested on patient groups and normal individuals.
How were the bacteria markers in the GA-map® Dysbiosis Test Lx selected?
Can the GA-map® Dysbiosis Test Lx be set up in my institution?
Yes. The GA-map® Dysbiosis Test Lx is available as a send-away service (send samples to our service laboratory in Oslo) or the technology can be set up in any laboratory. If you want to set up the GA-map Dysbiosis Test locally, we will assist you with every step to ensure that the transition is smooth and you get the most out of your testing.