Celebrating World Microbiome Day (27 June)

June 27 is World Microbiome Day – and we’re celebrating nearly 10,000 child stool samples!

You might wonder why we’re so excited about poo! Repeated samples help researchers study how child gut health develops.

This can have impacts far beyond the gut – such as mental health and obesity.

We caught up with Professor Richard Saffery, GenV Deputy Scientific Director, who leads GenV’s biosciences work, to hear more about GenV’s longitudinal stool sample collection.

What is your role at GenV and why did you get involved with GenV?

I am the Deputy Scientific Director of GenV. My role focuses on ensuring that the resource we build enables a range of possibilities in Biosciences. I have been involved in GenV since it’s very beginning. Over a decade ago!

My interest in large pregnancy and childhood cohorts began nearly 20 years ago. I was part of the establishment of the world’s first pregnancy study of twins, that followed families from pregnancy to adulthood. It involved a purpose-built biobank to enable a range of biological investigations.

Early life is when foundations are laid – particularly from a biological viewpoint. This is when biological processes unfold, often with lifelong consequences.  GenV provides a unique opportunity for researchers worldwide to explore how genetic, environmental, nutritional, and even social factors interact to shape child and parent health. It’s not just about identifying risk for disease, but also about understanding resilience: why some children thrive despite adversity.

Tell us a bit about the longitudinal child stool collection – What is it and how do participants take part in this?

The GenV longitudinal child stool collection or “child poo samples” involves collecting small samples of poo from GenV children who were born in the second year of GenV’s birthing window. These take-home kits were first given to families in hospital, shortly after their baby was born. Families were asked to collect a child poo sample (from their nappy) when their child was 7 days old. Over 7,500 of the 15,000 families approached gave samples from their newborns. These samples are safely stored at -80C in our state-of-the art biobank at The Royal Children’s Hospital. We are now following up with these families to provide a second sample from their now 2-year-old GenV child.

Why is studying the microbiome important?

The gut microbiome is the group of tiny germs (like bacteria) that live in our stomach and intestines. These germs help us digest food, fight off sickness, and keep our bodies working well. Babies don’t have many of these germs when they are born. But their gut fills with them quickly — from contact with their mother, the food they eat, and the world around them. This can influence their health outcomes for years to come. This is because the gut microbiome can affect many aspects of health, including growth, immune system (how the body fights infection or triggers allergy), and even brain development.

How will longitudinal child stool collection help the community?

Over the first two years of life, the gut microbiome goes through dramatic changes. This is due to environmental factors (such as diet). It gradually stabilises into a more adult-like state.

The kinds of microbes that end up in the gut can predict things like allergies, asthma, weight gain and depression. If we can understand when and how these changes happen, we might be able to help children stay healthier through simple changes to diet or by giving probiotics (helpful bacteria) at the right time.

How does longitudinal child stool collection fit in GenV and what does it add to science?

The GenV child poo samples collected over the first 2 years of life are amongst the largest collections of its kind worldwide. Poo is just one of many samples in the GenV biobank. This includes parent and child saliva, maternal blood samples following clinical testing in pregnancy, small blood spots from newborns following clinical screening, maternal swabs following clinic group B streptococcus testing in late pregnancy and breast milk.

Each sample provides different biological information — e.g. gut (stool), oral/genetic/stress (saliva), and total health (blood). Together, they give a more complete picture of health by showing how different systems interact.
They also may help researchers find early biomarkers for a range of pregnancy or child health outcomes. This helps see who might benefit from specific interventions, like dietary changes, probiotics, or stress reduction programs.

What have you found so far and what’s next?

Once poo collection is complete, we aim to create a complete picture of the microbes living in children’s guts soon after birth and how these change over the first 2 years of life. This is done by generating “gut metagenomes”, which are the complete DNA instructions of all the microbes in a sample. This data tells us what types of microbes exist and how many of each type there are. It also tells us what processes each is carrying out that may influence gut and general health.

What’s next for families?

We will continue to update you in our “GenV News” participant newsletter – keep an eye out for updates!

Provided a newborn sample? If you gave a newborn sample – we hope, you’ll collect another one. Look out for a stool kit in the mail around your child’s second birthday. Happy collecting!