Explore the GMAP Study

About the GMAP Study 

The Gastrointestinal Microbiome and Allergic Proctocolitis (GMAP) study is a prospective, observational, healthy infant cohort study created by a multidisciplinary team of doctors and scientists at Mass General for Children, in close partnership with Pediatrics at Newton-Wellesley. The study was designed to learn more about the earliest manifestations of food allergy in infants and the many factors that may contribute to the development of allergies or, conversely, tolerance acquisition.  

Starting in 2014, this long-term study enrolled children at their first pediatrics visit after birth and is following them through their entire childhood until they turn 18. We collect survey information, stool samples, blood samples, and urine samples at every pediatrics visit across the child’s lifespan to better answer many of these open research questions. 

Explore the topics here to learn more about GMAP, what we are learning from this exciting study, and how you can get involved. 

Exciting results from the GMAP study, published in Microbiome 2022.

Food Protein-induced Allergic Proctocolitis (FPIAP)

Food protein-induced allergic proctocolitis (FPIAP) is one of the earliest food allergic manifestations. It presents in young infants with fussiness, reflux behaviors, and blood/mucous in the stools. FPIAP is also referred to as cow’s milk protein intolerance or allergy (CMPA) or milk soy protein intolerance (MSPI). Very little research has been done on how this disease develops and the degree to which it does or does not predict later development of other food allergies. Dietary elimination of milk and soy proteins has been a mainstay of therapy, but little is known about the natural history of FPIAP or the long-term implications of this practice. 

Risk Factors 

We know that many factors may play a role in which children develop allergies or lose tolerance to certain foods. In the GMAP study, we aim to understand the role of environmental factors (e.g., mode of delivery, antibiotic use, pets), genetic factors, how and when foods are introduced into the diet, how those foods interact with the infant gut microbiome, and how this impacts long term health, well-being, and tolerance acquisition. 

Future Goals

We believe that a better foundational understanding of all these factors will lead to better clinical practice guidelines to help treat and ultimately prevent some pediatric food allergies.

Recent Podcast 

Check out this episode of Bowel Sounds, the Pediatric GI Podcast sponsored by the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN), where the team interviewed Dr. Martin about what we’ve learned from the GMAP study so far. 


(2023) Early infancy dysbiosis in food protein-induced enterocolitis syndrome: A prospective cohort study

(2023) Longitudinal assessment of early growth in children with IgE- and non-IgE-mediated food allergy in a healthy infant cohort. 

(2022) Food-specific immunoglobulin A does not correlate with natural tolerance to peanut or egg allergens. 

(2022) Longitudinal disease-associated gut microbiome differences in infants with food protein-induced allergic proctocolitis. 

(2022) EasyMap - An Interactive Web Tool for Evaluating and Comparing Associations of Clinical Variables and Microbiome Composition. 

(2022) Prospective associations between acid suppressive therapy and food allergy in early childhood.

(2022) In response to Frequency of guideline-defined cow's milk allergy symptoms in infants: Secondary analysis of EAT trial data by Vincent et al.

(2020) Increased IgE-Mediated Food Allergy With Food Protein-Induced Allergic Proctocolitis. 

(2020) Prospective Assessment of Pediatrician-Diagnosed Food Protein-Induced Allergic Proctocolitis by Gross or Occult Blood. 

(2018) Antibiotics and Acid-Suppressing Medications in Early Life and Allergic Disorders. 

View our full list of research publications from the GMAP study.

Contact Us

We’d love to hear from you! If you are a doctor, scientist, dietician, parent, or anyone who is interested in becoming more involved in the work we are doing, please email us at mghgmapstudy@mgb.org. We love to collaborate and can learn a lot more together!