by Ashleigh Feltham,  Accredited Practising Dietitian and Accredited Nutritionist

Genes Influence Gut Microbe Function. Genes are the sequences of DNA that determine biological and physical traits. Not only do genes dictate things like eye colour and skin tone, but also whether you would have diseases such as autoimmune from birth. Genes also influence your risk of developing diseases like cancer. New research adds another role that your genes play: influencing how microbes function.

Your microbiome is made up of the microbes that live in your gut. This includes fungi, bacteria and viruses. There are up to about 500 different types of bacteria that live in the gut, totaling approximately 39 trillion microbes. Every person has a different gut microbiome as unique as their fingerprint.

There are many factors that influence the gut microbiome. These include gender, medication, stress, exercise and diet. This new research looks specifically at how your microbes function.

Influencing the function of the microbiome ultimately affects the health of your body. Microbes influence many components of your health including the ability of the immune system to function at its best, the risk of psychiatric conditions and certain cancers.

Researchers used the TwinsUK cohort study to investigate the potential effects of genes on the gut microbiome. Two hundred and fifty female twins were selected as participants. The genes of each individual were assessed, as well as disorders associated with microbiome disruption to healthy and normal functioning; conditions like certain cancers, type 2 diabetes and certain brain disorders.

It was found that each individual’s genes affected the ability of their microbes to function, including the secretion system. The secretion system produces chemical messages in the form of SCFAs (short chain fatty acids). SCFAs benefit almost all organs in the body. Genes also determined if microbes became antibiotic resistant.

In addition to these interesting findings, researchers found associations between genes and specific types of microbes not previously known. This included the strains Bifidobacterium, Akkermansia and Faecalibacterium. This research also supported previous findings that genes influenced the function of the microbe strain Faecalibacterium prauznitsii.

This research adds to the strength of past findings that genes do influence how the gut microbiome functions.

There is good news. While you may not be able to change your genes, you can influence how your genes will respond with lifestyle factors such as diet. A diet that promotes healthy microbes can change your health outcomes.

Lifestyle habits you can add into your week to support better health include:

1. Adding 30 different plant-based foods a week. This includes foods like wholegrains, nuts, seeds, legumes, vegetables and fruit. Different microbes need different fuel sources. Include a variety of plant foods to ensure you feed all of them.
2. Meet your recommended dietary fibre needs. For an adult, this is 25-38g of dietary fibre each day. Adding plant food to all snacks and meals will help you to meet your needs.
3. Add two serves of probiotic-rich foods each day. This includes miso, tempeh, kimchi, yoghurt and sauerkraut.
4. Include fatty fish like salmon, sardines, herring and mackerel two to three times a week. These fatty fish contain omega-3 fats, which have potent anti-inflammatory properties that support good health in many ways, including the health of your gut.

Take home message:

Genes Influence Gut Microbe Function. While you cannot change your genes, this research reveals how we can provide tailored, individualised support to help your microbes function at their best.

References:

1. National Human Genome Research Institute.
2. New, F.N., Baer, B.R., Clark, A.G. et al. Collective effects of human genomic variation on microbiome function. Sci Rep 12, 3839 (2022).
3. What Your Gut Bacteria Say About You. WebMD. https://www.webmd.com/digestive-disorders/what-your-gut-bacteria-say-your-health
4. The human microbiome: Everything you need to know about the 39 trillion microbes that call our bodies home. Science Focus.
5. A person’s genetics can shape gut microbiota functions. Microbiome Post Exploring Research, Inspiring Clinical Practice.
6. The Norwegian University of Science and Technology (NTNU). “Feed your genes: How our genes respond to the foods we eat.” ScienceDaily. ScienceDaily, 20 September 2011.