Genome Environment Microbiome and Metabolome in Autism Study (GEMMA)

April 14, 2026 updated by: Alessio Fasano, Massachusetts General Hospital

Genome Environment Microbiome and Metabolome in Autism

GEMMA is a multicenter longitudinal observational study that follows children who are genetically at-risk of developing autism for their first three years of life, seeking to identify potential biomarkers predictive of autism development in the blood, stool, urine and saliva. The biomarkers identified in this project will contribute to a better understanding of the pathogenesis of ASD in at-risk children and possible solutions for alleviating and/or preventing ASD and ASD-related symptoms in patients in the future.

Study Overview

Status

Completed

Detailed Description

The GEMMA study will address genomic, environmental, microbiome, and metabolomic factors that may affect the development of autism spectrum disorders (ASD).

Genome: The project will study children who have a first-degree relative (sibling) with ASD so that investigators can understand how their genes may contribute to whether they develop ASD or not. A number of genetic variants identified to date occur in genes encoding glycosylated extracellular proteins and in enzymes directly involved in glycosylation. Investigators will perform whole genome sequencing in the subgroup of children that will develop ASD in order to learn more about these specific genes and also to identify other genes that may be involved in ASD pathogenesis. The genetic variant landscape will be mapped and variants will be annotated and interpreted based on all contextual information available. This effort will enable the identification of patient- and cohort-specific variations that can then be further refined into biomarker signatures and optimized into predictive and diagnostic markers of ASD.

Environment: When infants enroll in the study, investigators will record information about their environment including whether they were born vaginally or by Cesarean section and whether they have received antibiotics. Over time, investigators will also consider other parts of the infant's medical, dietary and social history including feeding modality (breastfeeding versus formula feeding), illnesses, infections, antibiotic use, diet and growth to understand whether any of this information is related to ASD development. This data will be updated monthly until each enrolled infant reaches 3 years of age, yielding a valuable compilation of information that will provide insight on how environmental changes affect whether the child develops ASD or not.

Microbiome: The human gut, compromised of the small and large intestine, is home to many types of bacteria. These bacteria help to break down and digest food, provide the body with energy, and make vitamins that the body need to thrive. This diverse community of bacteria is called the gut microbiome, which is known to play a large role in the development of the immune system. A main goal of the GEMMA study is to understand how the microbiome is affected by factors such as food intake or antibiotic drugs, and how this may affect the development of ASD. Investigators hope to learn more about this relationship by studying the members of the gut microbiome before and after autism development in the subset of enrolled infants who will develop ASD. The project will compare microbiota of ASD children with and without GI symptoms to determine whether different microbiota composition and differentially expressed bacterial genome perturb intestinal barrier function and immune response, leading to ASD in genetically at-risk infants. By doing this, the project will uncover patterns in the gut microbiome that may help investigators to predict who will develop ASD before it happens.

Metabolome: The processes that occur in the gut, such as the digestion of foods and production of vitamins, create products that are called metabolites. The specific metabolites that humans produce differ from person to person and depend on many factors, including genes, members of the gut microbiome, and food choices. The collection of metabolites produced by a sample is called the metabolome. The project will study the metabolomes of different infants while taking note of any changes to their environment and monitoring them for ASD. Studying the metabolites in this way is called metabolomics. In doing this, investigators hope to find patterns, or specific metabolomic profiles, that might predict when someone may develop ASD before it happens.

Study Type

Observational

Enrollment (Actual)

344

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Galway, Ireland, H91 TK33
        • National University of Ireland Galway
      • Salerno, Italy, 84124
        • The Azienda Sanitaria Locale Salerno
    • Massachusetts
      • Boston, Massachusetts, United States, 02114
        • Massachusetts General Hospital for Children

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

No older than 6 months (Child)

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

Newborns and infants less than 6 months of age who are first-degree relatives of ASD individuals (at least one sibling with an ASD diagnosis) are eligible for participation.

Description

Inclusion Criteria:

  • Healthy newborns and infants less than 6 months of age who have not been introduced to solid foods (elementary formula feeding is permitted)
  • First-degree relatives of ASD individuals (at least one sibling affected by ASD)

Exclusion Criteria:

  • Infants older than 6 months of age
  • Inability or unwillingness of legal guardian/representative to give written informed consent

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Infants with ASD-affected sibling
Infants, enrolled at 0-6 months of age, who have a sibling diagnosed with ASD.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Use of microbiome/metagenomics/metatrancriptomic analysis to identify through our proposed prospective study and validate through large existing microbiome projects multi-omic biomarker predictors of ASD in at-risk infants.
Time Frame: 5 years
i.e. stool and urine metabolites, alteration of gut permeability (via serum zonulin levels), abnormal immune response to dietary proteins (via IgA and IgG levels) and increased low-grade chronic inflammation (via serum pro-inflammatory cytokines).
5 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Alessio Fasano, MD, Massachusetts General Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

July 1, 2019

Primary Completion (Actual)

December 31, 2025

Study Completion (Actual)

December 31, 2025

Study Registration Dates

First Submitted

February 12, 2020

First Submitted That Met QC Criteria

February 13, 2020

First Posted (Actual)

February 17, 2020

Study Record Updates

Last Update Posted (Actual)

April 15, 2026

Last Update Submitted That Met QC Criteria

April 14, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Autism Spectrum Disorder

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