New first-of-its-kind research provides insights into an important health-boosting ingredient of human breast milk.
A team led by Dr. Qingling Duan, Queen's University’s National Scholar in Bioinformatics, partnered on the groundbreaking research in CHILD Cohort Study (CHILD). The major, multi-year collaboration connected breastmilk researchers at the University of California San Diego and the University of Manitoba with bioinformatics and computational genomics experts at Queen’s University.
Published in Nature Communications, their research sheds light on the complex relationships among a mother’s genetic makeup, the human milk oligosaccharides or HMOs (an abundant and diverse group of sugars) in her breastmilk and her baby’s respiratory health.
The study’s findings could inform new ways of predicting and preventing childhood disease and could facilitate new HMO-based therapies to prevent respiratory illness.
“These insights may allow us to develop HMO-inspired supplements for babies and to bioengineer specific HMOs for use in research—eventually perhaps even for use in therapies to treat respiratory diseases, in both children and adults,” says lead author Amirtha Ambalavanan, a postdoctoral research fellow in Biomedical & Molecular Sciences at Queen's University. “We have so much to learn from human milk.”
The researchers conducted genome-wide association studies (GWASs), which simultaneously looked at millions of DNA sequence variations and how they relate to varying concentrations of 19 different HMOs found in the milk of 980 mothers participating in CHILD. They then looked at whether exposure to these differences in HMOs were associated with risk of developing recurrent wheeze, an early symptom of asthma, among the breast-fed babies. Dr. Duan’s team identified strongly correlated genetic variations among the moms and the HMO composition of their milk.
“My team was blown away by the significance of the GWAS signals between the maternal genomes and their HMO profiles,” notes Dr. Duan, also an associate professor in the Department of Biomedical and Molecular Sciences and the School of Computing at Queen’s. “Moreover, while we had expected some associated loci, our study identified a number of novel genetic associations previously not known to be involved in HMO production.”
To test the strength of these findings, they conducted the same analysis in 395 mothers from another cohort, the INSPIRE Study, and found many of the same associations.
When it came to tracing the impact of HMOs on the babies’ later respiratory health, the researchers found that milk with different HMO profiles appeared to affect childhood respiratory outcomes—sometimes even overriding the risk carried in the children’s genes. Milk with high levels of specific HMOs tends to protect babies against later developing wheeze. This impact is particularly evident among children with high genetic risk of developing asthma.
By increasing our knowledge about how HMOs are produced and how they influence health, the study points to possible new advances in healthcare and medical research.
“The more we know about HMOs, how they are synthesized and what impact they have on human health, the better we can design helpful interventions to prevent childhood diseases,” says Ambalavanan.
“Of course, we already know that breastfeeding provides many amazing health benefits,” comments co-author and CHILD Deputy Director Dr. Meghan Azad, a leading breastmilk researcher and Canada Research Chair based at the University of Manitoba.
“But we don’t fully understand how this works at the biological level. Here we explored the complex dynamics among mothers, their milk and their babies to see how a mom’s genes influence the composition of HMOs in her milk, and how these HMOs interact with her baby’s genetics to influence their risk of later developing asthma.”
This story was first published by Queen's Health Sciences