Timothy Caulfield’s article, “Microbiome research needs a gut check” published in the Globe and Mail, reminds us of just where we’re at in researching the microbiome – the vast array of bacteria, fungi, protozoa and viruses that live on and inside the human body. “Gut hype is everywhere” says Caulfield, who is one of many voices cautioning about over simplistic media coverage and aggressive marketing of “bunk” products and ideas that exploit and undermine the important scientific research underway.
There is growing evidence that the microbiome can be linked to a variety of health conditions including asthma, autism, diabetes and cancer. When you look beyond the hype, there is real potential. Unravelling the mystery of microbial ecosystems may lead to more personalized treatments of disease (and prevention) either through direct manipulation of the microbiome, or through food and its interaction with the microbiome.
One initiative, funded in part by Genome BC, is exploring the impact of the microbiome on the development of childhood asthma. The project is led by Stuart Turvey, a pediatrician specializing in allergy and immunology at BC Children’s Hospital Research Institute. Turvey is also one of the co-leaders of the Canadian Healthy Infant Longitudinal Development (CHILD) study, following 3,500 Canadian children in the hopes of identifying the root causes of asthma.
Children who grow up on farms, have a couple of older siblings, or go to daycare, where they are exposed to bacteria and viruses early in life, seem to have a lower risk for developing asthma. While children born through Caesarian section, missing exposure to their mother’s vaginal birth canal, or babies who are given antibiotics, which reduce the diversity of bacteria in the gut, seem to be at a higher risk.
However, preventing asthma isn’t as simple as having a larger family, growing up on a farm, or avoiding antibiotics and antibacterial soaps. There is still very much to learn about the symbiotic relationship we have with the microbial ecosystems. Any observed correlations between the microbiome and various health conditions, while promising, have not definitively established a cause and effect relationship and initial observations need to be confirmed through further research.
As part of the CHILD study, stool samples were collected from children at birth, three months of age and one year. When some of these children began to develop asthma as they grew, researchers were prompted to examine the early stool samples (frozen in the lab) to see if there was something different in their microbial ecosystem. What they found (or more accurately, didn’t find) may have opened the door to preventing asthma. The team was able to discover the absence of four bacteria: Faecalibacterium, Lachnospira, Veillonella and Rothia (FLVR). The absence of these four bacteria, which can be detected at as early as three months of age, suggests the child may be at higher risk for developing asthma.
But the relationship between the microbiome and our health is complex because everyone’s microbiome is unique – like a fingerprint. Understanding which microbes are present or not present is an important part of the puzzle, but so is understanding the functional aspects of the microbes that are there and how this relates to health.
Turvey and his team are using genetic sequencing to confirm their previous findings and to examine the entire microbiome to determine once and for all if these missing microbes are leading to asthma, and if so, look at developing ways to replace these missing microbes. Caulfield is also part of this project by examining the development of responsible and safe ways to replace these missing microbes, if that is where the science leads.
This is also what Dr. Deborah Money, the Executive Vice-Dean of the Faculty of Medicine at University of British Columbia and a Professor in the Departments of Obstetrics and Gynecology is doing. In Canada 1 in 4 women have a caesarean delivery. While there is some evidence of increased risk of asthma, (and other conditions) in caesarean-born infants, a clear link between delivery type and the infant’s bacterial community has not been established.
Money has embarked on a program to study the role of the maternal microbiome in establishing the infant gut microbiome. This study will profile the bacterial communities present in women who deliver vaginally or via caesarean section and connect these to the infant gut bacterial community in the first three months of life. This research will lead to a deeper understanding of the potential role of the maternal bacterial community on the infant gut bacterial community.
These initiatives are among many studies around the world, methodically and responsibly building an improved functional understanding of the human microbiome. While hype can be dangerous and misleading, hopefully the strong interest in this science can be channeled into something positive ― like developing an understanding of the human microbiome and its link to health and disease, which is the basis for successful translation of research projects into credible health, clinical and commercial applications.