On Mother’s Day, we celebrate the bonds that connect mothers and their children: the stories, traits and memories that are passed down each generation. But could this connection go beyond to what we can see with the naked eye? In the Isala daughter study named Maggie we are exploring whether microbial companions are also passed down by our mothers and shared within a family.
From swabs to family microbes
We share many traits with our families, from eye colour to facial features. But could we also share bacteria with the people closest to us? This question has fascinated me throughout my PhD. As a bioinformatician and the leading force behind the Maggie project, I spend my time moving between two different worlds in the field of microbiology. One moment, I’m discussing study logistics with colleagues. The next, I’m typing away on my computer analyzing millions of DNA fragments to explore the fascinating bacterial communities that live inside the vaginas of our Isala participants. While these analyses might sound a bit chaotic, it’s one of the things I love the most about this work. Every sample tells a story and represents a woman who chose to contribute to science.
Fig. 1: On the left, bioinformatics analyses at work; on the right, the Maggie sampling boxes ready for participants.
One of the most fascinating stories hidden in these samples started with mothers and daughters who participated in Isala together. Their contribution sparked a simple but intriguing question within our team: could mothers and daughters share vaginal bacteria? As highlighted in Margo’s blog, our first analyses suggested they might! We found that some mothers and daughters carried remarkably similar bacteria in their vaginas. But were they actually sharing the same vaginal bacterial strains?
Meet the members of the microbial family
Just like every family has its own story, bacteria also belong to families. A species is like a family name: members of the same family share many characteristics. But within each family, every individual is unique. These individual versions are called strains. Although strains of the same species are closely related, they can differ in important ways, such as the genes they carry or the substances they produce. Some strains may help protect our health, while others have little effect or may even contribute to disease. That’s why being able to distinguish strains, and not just species, is so valuable for understanding the microbiome.
A mother’s microbial legacy
To answer that question, we needed to take a closer look at the samples. Using a technique called ‘high-resolution metagenomics’, we could zoom in on the vaginal microbiome and read the DNA of all microorganisms present in a sample. This allowed us not only to see which bacterial genera were there (like in the first phase of Isala), but also to explore their specific genetic characteristics and potential functions. And that’s where things became really interesting 😊 With this high-resolution approach, we found that some mother-daughter pairs from Isala shared the same vaginal bacterial strain, not just the same species! Amazing, right? To explore the science behind these findings, be sure to check out our latest pre-print.
Fig. 2: From a vaginal swab to a detailed characterization of the vaginal microbiome: DNA extraction, sequencing and computational analysis.
As a researcher, these are the moments that make all the work worthwhile: when a tiny detail reveals a much bigger story. Suddenly, one finding sparks a whole new set of questions. How far does this microbial sharing extend? Could some vaginal bacteria be passed from mother to daughter and remain with them for decades? Do our genes play a role, or are shared environments equally important? The honest answer is that we don’t know yet. But discoveries like these remind us how much there is still to learn about the vaginal microbiome. Most importantly, they inspired the next chapter of the Isala story: Maggie.
One of Isala’s daughters: Maggie
In this Isala daughter study, Maggie, we explore the story of the vaginal microbiome across generations, investigating how these microbial communities are shared between mothers, daughters, and loved ones. By studying these families specifically, we hope to uncover how the vaginal microbiome grows and changes alongside us, from childhood into adulthood. This will help build foundations for future breakthroughs in women’s health.
The inspiration behind the name: Margaret Dayhoff
You may also be wondering where the name Maggie comes from. The study is named after Margaret Dayhoff (1925 – 1983), the founder of bioinformatics. Her groundbreaking work helped shape a scientific discipline that continues to transform research today. Like many women in science, Margaret (Maggie) faced challenges along her career path. After taking a break from research to care for her two daughters, she was told that she had been away from science for too long. Fortunately, someone saw what others had missed. Today, her story reminds us that supporting women in science can leave a lasting impact for generations to come.
In 2025, we took this a step further in by studying a new group of women in Flanders. What started with a goal of recruiting 60 mothers and daughters soon grew beyond expectations, thanks to the enthusiasm and commitment of our amazing volunteers. We were also able to include a wide variety of co-participants in our study: sisters, grandmothers with their granddaughters, nieces, and maternal aunts. All collected samples were processed in the Isala lab, and soon we will begin mapping out the bacteria they contain, so keep an eye out for any updates on the Isala website!
In September, we will continue our search for the microbial links that connect mothers and daughters across generations. To make the next discoveries possible, we are looking for new volunteers to join the Maggie study. Ready to make a difference together with your family? Register here and become part of the next chapter of Maggie’s research. Your participation could help unlock the next breakthrough in women’s microbiome science 😊
Who am I?
My name is Maria and I am a third-year PhD student with a background in microbiology and bioinformatics. As a proud member of the Isala team, my research explores how ecological and evolutionary processes shape the vaginal microbiome. Thus, one of the key questions driving my PhD research is whether vaginal bacteria can be shared between genetically related women. This is where the Maggie project comes in. By studying mother-daughter pairs, I aim to better understand how the vaginal microbiome is shaped and maintained across generations. Ultimately, I hope this knowledge will contribute to new strategies that promote the transfer of beneficial bacteria and support women’s health across generations.