“I think you would be hard-pressed to find any disease that microbiome is not linked to at the moment.” Rachel Purcell commented when I joined her for a discussion about her research. Our microbiome is the genetic material from all the microbes that live in the human body, including bacteria, fungi, protozoa and fungi. The gut microbiome focuses on just those organisms found in the gastrointestinal tract. This is where Rachel’s research sits. She is interested in how the microbiome affects various disorders. This is mainly colorectal cancer, but also includes diseases such as diverticulitis, appendicitis, and IBD. Her specific area of interest at the moment is how the tumour microbiome, or the gut microbiome, influence the bodies responses. The microbiome may have an effect on the progression of the disease, or influence treatment methods.
Rachel explained that the gut microbiome is well characterised, and we have a good idea of what microbes are present. Rachel uses a technique called RNA-Seq, which allows her team to catalogue what is present, with the added benefit of providing information about the functions that microbes might perform. Rachel explained “microbiomes are very unique, and simply counting what is there is not giving us a good idea of what they are doing. Our approach is to look for functional links and then form our computational data, then we can pull things out, and then design experiments that we can carry out in the lab to see whether any of those actually reflect what we see in the sequencing data.” Rachel also explained “there is quite a lot of redundancy of function. Two people can have completely different microbiomes, but they can both function the same. We are trying to not just look at the ‘bugs’ but look at the function. We do try to resolve it down to the species level sometimes because you need to do that for lab work, but there is such a crossover.”
Characterising different microbiomes in all types of patients and getting an idea of what functions they might perform, is paving the way to understanding how our gut microbiome might affect our susceptibility to disease, and possibly treatment. Rachel explained that although this research is in its infancy, there are certainly possible treatments that can arise from the research. “With microbiome, there is always the possibility of manipulating it, which is a lot easier than trying to change our host genomes or our host responses. Even looking at what has been done so far, there is definitely a lot of potential for the therapies, I think.”
Background
Rachel grew up in Ireland and has done her fair share of globe-trotting. Her travels have left her fluent in English and French, she also speaks a little Italian and Spanish, and a little Te Reo. Growing up in Ireland, Rachel reflected on her education in convent schools “studying science in a school where a lot of the text was redacted, definitely piqued my interest. I had a nun teaching me science and it was the strangest experience. A lot of things we glossed over, I thought ‘l want to know what this is about’. For a long time, I wanted to be a scientist, from a very early age.” In line with this plan, Rachel completed a Medical Laboratory Science and then a Biomed honours degree from University College Cork.
An opportunity presented itself for Rachel to attend the Pasteur Institution, an internationally renowned biomedical research institution in France. She completed her masters in bacterial genomics here, joking about the time “way back when it took two years to sequence the bacterial genome.” This research is where Rachels interest in bacterial genomics began. Following her master, however, she followed her interest in cancer research and went on to work in diagnostic cancer labs. “But I was always keeping an eye on what was going on in the bacterial genomics field and it was cool to be able to put the two things together—micro and cancer genomics. I guess I have a background in both because when I went back to work in diagnostics it was always in histopathology, and always looking at cancers.”
Seeking a change of location, and wanting to emigrate somewhere that spoke English, Rachel and her husband opted for New Zealand over Canada. She has been here for over sixteen years and raised her children here. She now resides in Arthur’s pass, enjoying the scenery and the calls of Kiwi in the night.
Colorectal Cancer
When I quizzed Rachel on which burning question she would most like answered, she responded “It would have to be about cancer prevention. Can we actually prevent a lot of the cancers that we are seeing? Here and everywhere, I do not think we are putting enough effort and research into prevention. We are targeting the wrong end of cancer, trying to treat people and come up with different solutions. If I could do anything, it would be in the preventative space. For example, trying to predict who is going to get these cancers, particularly sporadic cancers, and some way that we can prevent them. Whether it is by targeting the microbiome with faecal microbiome transplants, or even food interventions. I would love to think that that was going to be the way of the future.”
Rachel suggested that screening from a young age would be a beneficial step. “Because we are seeing quite an increase, particularly in colorectal cancers, in younger people now, under the age of 40-50, which we did not see many of before—it used to be a disease of old people. I mean, it has got to be something lifestyle-related. It is not going to be hereditary with the way things are changing so quickly, and I think the most obvious thing is what we are taking into our bodies, our food, and our diet, in general, has changed so much over the last 30-40 years.
Rachel also explained that simply screening people and informing them of a cancer risk would be inadequate, particularly if diet changes are a part of treatment.” When it comes to diet, a lot of it is social as well, and down to education. It is not just about trying to put interventions in place, it is a whole package.”
Education
Education was a theme that came up in my discussion with Rachel. Although her research does not involve genetic engineering, many people associate genetics research with genetic modification. I asked Rachel how well educated the public is on these matters. “In New Zealand, we are lagging behind, and there is a hangover of fear about genetic engineering…I think some of it is probably political. People do not understand that much of what we eat, use, and grow is genetically engineered. The idea that it is three-headed fish and stuff, it is an issue around education for sure. We are not doing that very well… we are very far behind.”
In regard to how we might go about instilling confidence in genetics research in the public, Rachel suggested “we need more education, right from kids in school, about how to assess where they are getting their information from. With the internet, you type something in and take the first hit. You do not know how to tell if your information is correct, or whether it is an imbalanced source, that is such an issue these days. Many people get their information from social media, which is scary. As scientists, we used to have public trust, and we were the voice of reason and truth, but that is all changed with social media platforms. Scientists are not present enough in that space, fighting the mystery. Part of our job now is to fill the void, because if we do not fill the void, it is filled with rubbish. A lot of us probably thought, in a sense, we were above that. We actually have to get down and dirty with the public. We have got to start from a young age. Kids need to learn how to actually evaluate the information that is out there, and I do not think that is happening.”
With the possible implications of her research, and the possibility of preventing cancer, it is understandably frustrating that the public is still lagging behind in their understandings of what genetics research is, how it works, and the benefits it could provide. In Rachel’s words, “I think it is time for change.”
Written by Don Sinclair
Images Supplied by Rachel Purcell
