Gene variants help explain why food allergies run in families

DALLAS – Feb. 19, 2026 – People often remark that allergies run in their family, but the genetic causes have remained unclear. Previous food allergy genetic research has relied upon broad but surface-level methods called genome-wide association studies.

Now, for the first time, a study at UT Southwestern Medical Center uses an in-depth genetic approach to explain why food allergies are inherited and why some people develop multiple food allergies. The findings, published in The Journal of Allergy and Clinical Immunology, suggest that more comprehensive genetic testing could support better approaches to diagnosing and treating food allergies.

“This research shows that advanced DNA testing can uncover clear genetic causes in nearly 4 out of 10 people with multiple food allergies,” said corresponding author Jeffrey A. SoRelle, M.D., Assistant Professor of Pathology and Pediatrics at UT Southwestern.

Food allergies affect an estimated 33 million Americans and lead to about 3.4 million emergency room visits each year due to anaphylaxis, yet treatment options remain limited.

The latest work builds on previous basic science research by Dr. SoRelle and UTSW colleagues that had demonstrated a strong genetic contribution to allergic disease and indicated that many high-impact allergy genes remain undiscovered.

The new study recruited patients at the Food Allergy Center at Children’s Health who were evaluated by J. Andrew “Drew” Bird, M.D., the Center’s Director and a Professor of Pediatrics and Internal Medicine at UT Southwestern. These patients had confirmed allergies to two or more foods, a group believed to carry a higher inherited risk than those allergic to only one food.

Using whole exome sequencing – a technique that examines the protein-coding regions of genes – the researchers analyzed DNA from 56 patients and their family members (when available). Nearly 40% carried a rare loss-of-function mutation in a gene known to increase allergy risk.

Most of the mutations involved FLG, a gene that helps maintain the skin’s protective barrier. When that barrier weakens, allergens may enter the body more easily and trigger immune responses. The study found that comprehensive genetic testing identified 58% more FLG mutations than traditional genotyping approaches and included variants often missed by older genetic tests, particularly in patients of non-European ancestry.

In addition, the researchers identified rare mutations in immune-related genes, including one involved in viral sensing. These findings suggest a possible genetic link between food allergy risk and the immune system’s response to infections, offering new insight into the long-standing hypothesis that early exposure to infections can boost the immune system.

“This study shows that we should be doing more sequencing in the field of food allergy, including for clinical trials and in research centers,” Dr. SoRelle said. 

Moving forward, the team plans to expand the research through UTSW’s Sequencing Populations to Accelerate Research and Care (SPARC) program that launched in 2025 to investigate how specific genetic variants influence disease course and treatment response.

Ultimately, the broader use of comprehensive genetic testing could help move food allergy care toward a more precise, individualized approach that reflects the underlying biology of a condition affecting millions of families. 

Other UTSW researchers who contributed to this study are first author Anas M. Khanshour, Ph.D., Data Scientist; Cynthia Haddad, M.D., clinical allergy fellow; Melissa Zamudio and Amy Arneson, RN, B.S.N., clinical research coordinators in Pediatrics; and Dr. Bird, who also serves as Interim Chief of the Division of Pediatric Allergy and Immunology at UTSW and is a Dedman Family Scholar in Clinical Care.

Dr. Bird has served as a consultant in the past 36 months for Allakos, DBV Technologies, Food Allergy Research & Education (FARE), Genentech, Hanimune Therapeutics, Infinant Health, Novartis, and Parexel. He has received research support from Abbott, Aimmune, ALK, DBV Technologies, FARE, Genentech, the National Institutes of Health/National Institute of Allergy and Infectious Diseases (NIH/NIAID), Novartis, Regeneron, and Siolta Therapeutics. He serves in uncompensated roles as Chair of the Executive Committee of the Section on Allergy and Immunology of the American Academy of Pediatrics, as a medical advisory board member for the International FPIES Association, as an independent study monitor for Vedanta, and as past Chair of the Stock Epinephrine Advisory Committee for the Texas Department of State Health Services.

Dr. SoRelle has financial relationships with Cereus Diagnostics Inc. and ENU Medicines and has received research grant support from the National Institutes of Health, Disease Oriented Clinical Scholars Program, and Thrasher Research Foundation.

About UT Southwestern Medical Center

UT Southwestern, one of the nation’s premier academic medical centers, integrates pioneering biomedical research with exceptional clinical care and education. The institution’s faculty members have received six Nobel Prizes and include 24 members of the National Academy of Sciences, 25 members of the National Academy of Medicine, and 13 Howard Hughes Medical Institute Investigators. The full-time faculty of more than 3,300 is responsible for groundbreaking medical advances and is committed to translating science-driven research quickly to new clinical treatments. UT Southwestern physicians in more than 80 specialties care for more than 143,000 hospitalized patients, attend to more than 470,000 emergency room cases, and oversee nearly 5.3 million outpatient visits a year.