P042. Microbiota stability in vivo and in vitro
F.T. Hegge1, H. Vebø1, E. Ciemniejewska1, C. Frøyland1, S. Kreso1, M. Sekelja1, A. Røseth2, C. Casen1, 1Genetic Analysis AS, Development, Oslo, Norway, 2Lovisenberg Diakonale Hospital, Unger-Vetlesens Institute, Oslo, Norway
Genetic Analysis AS (Oslo, Norway) has developed a proprietary technology for analysis of gut microbiota in humans. The technology enable simultaneous detection of >100 bacteria using a DNA probe methodology that utilizes common and variable DNA sequences within the 16s rRNA gene. The technology is currently being commercialized as an IBS dysbiosis test.
As faecal samples for commercial testing most often are collected at home by the patient, the sample has to be transported from the collection site to the analysis laboratory. This transportation might take several days, in which the sample is stored in a sample collection tube. During this period both microbial growth and DNA degradation can occur, altering the 16S rRNA gene composition of the sample. GA has investigated how the gut microbiota develops over time in a sample collection tube without any stabilizing buffer.
In addition, a person's microbiota is expected to exhibit natural variation over time. This variation occur even without the influence of travel, diet or medication (antibiotics). GA has investigated the normal variation (intra-person variation) in microbiota over multiple sampling points over several months.
For the storage/transport testing, eight healthy persons donated samples. A further analysis included 10 dysbiotic samples. For the intra-person testing five volunteers have been collecting samples regularly over a period of 12 weeks. The volunteers have been living “normal” lives. All samples were analysed using the GA-map™ IBS dysbiosis test.
Using the GA-map™ IBS Dysbiosis Test no difference in bacterial composition was seen after 8 days at room temperature. Furthermore, using the GA-map™ IBS Dysbiosis Test it has been demonstrated that each person's microbiota vary less over time than variation between healthy persons. I.e. each person's microbiota is unique and stable over 12 weeks.
It is important to remember that these studies are performed using the GA-map™ IBS Dysbiosis Test and limited to the bacterial sub-population detected by this test.
The sampling of feces for use in the GA-map™ IBS Dysbiosis Test can be performed up to five days prior to freezing at −20°C until further analysis.
The natural variation occurring in persons living “normal” lives do not influence the results of the GA-map™ IBS Dysbiosis Test. (i.e. the inter-person variations dominate the intra-person variations). The microbial fingerprint of each individual is recognizable and specific over time.