December 21, 2023

The intersection of genetics and environment: MHWFAC launches new long-term sibling study

Why do some kids develop food allergy, while others, even those in the same family, do not? Why has food allergy in children doubled in just the past 20 years? 

Unraveling those mysteries is the aim of a new long-range study being launched by the Mary H. Weiser Food Allergy Center. 

And unlike some research, where investigators look at people with established food allergy diagnoses, this project will enroll participants even before they are born. 

The Michigan Sibling Immunity Birth Study (M-SIBS) will begin recruiting pregnant subjects in early 2024 and will follow the newborns from birth to age three, periodically collecting samples and health information from baby, parents and siblings. 

“The aim of M-SIBS is to evaluate early life factors that lead to the development of food allergy,” said the project’s director, Kelly O’Shea, MD.  As an allergist at Michigan Medicine and assistant research professor at the MHWFAC, she cares for patients with food allergy as well as conducting scientific research and clinical trials.

Birth cohort research is emerging as a tool to investigate food allergy disorders, which tend to appear in children by the time they are two years old, said Dr. O’Shea. “There is a clear interplay between genetics and environment; we plan to tease out markers in both areas by looking at factors from familial allergy history, the home environment, and the participants’ genetic signatures as well as microbiome.”

For example, she noted, if a sibling has food allergy, a younger sibling has approximately double the average likelihood of having food allergy as well.  Among monozygotic (identical) twins, there is a 65 percent chance that if one has food allergy, the other will, too. 

The M-SIBS program will aim to recruit 1,000 pregnant women and their babies over the next three to four years, from among Michigan Medicine patients. To qualify, the newborns must have one first-degree relative (parent, sibling) with an atopic disease such as asthma, seasonal allergies, or eczema. 

Researchers will take biological samples and survey data from birth and continue to follow the participants intermittently until age three..  The children will be evaluated for eczema, a known precursor to food allergy, and tested for food sensitivities starting at five months.  

Parents and siblings also will give samples on one occasion. Subjects will be visited at home and surveyed periodically about health and environmental factors. 

Participating families will benefit either by having food allergy ruled out, or accurately diagnosed at an early stage in the child’s development, so that parents can take appropriate precautions.  The research will fill gaps in scientific knowledge regarding the early life development of food allergy and provide investigators with ideas for new treatments and therapies. The biological and environmental samples will be stored for future use by researchers, as well.

Dr. O’Shea is building out the study team, which now includes experts in obstetrics and gynecology, epidemiology, genetics, allergy and immunology as well as clinical coordinators, data managers, statisticians, and experts in basic and translational research. 

“We’re very excited to be taking this deep look at food allergy at the genetic level,” she said.  “We will fully analyze the early-life gene-environment interactions that lead to the development of food allergy. With this comprehensive multi-omic model, we intend to discover new potential targets for intervention and areas to focus on prevention in the field of food allergy.”


A multi-omic approach to food allergy

M-SIBS investigators will collect biological samples from study participants and analyze them using state-of-the-art techniques.  The ‘multi-omics’ approach will assess the interplay of various factors at the molecular level, including:

Genetic: The overall study of an individual’s DNA

Epigenetic: How environmental variations of the DNA affect the way hereditary factors develop

Transcriptomic: How the DNA is expressed  

Microbiomic: The organisms that live in the human body, including bacteria, fungi and viruses

Proteomic: How proteins are expressed

Environmental:  Exposure to a variety of factors, from cigarette smoke to dust