Skip to main content
IDF logo

Nijmegen breakage syndrome

Related gene: NBN

Inheritance pattern: Autosomal recessive

Variants in the NBN gene, which codes for a protein called nibrin, cause Nijmegen breakage syndrome (NBS), a chromosomal instability condition. Deficiency of nibrin leads to poor ability to repair DNA. As a result, affected individuals are highly sensitive to the effects of sunlight and radiation, or any substance that can cause breaks in DNA. The inability to repair DNA has many associated complications, including short stature, small head size (microcephaly), distinctive facial features, combined B and T cell immunodeficiency, an increased risk of cancer, and mild intellectual disability. Individuals with NBS have a propensity for infections, particularly sinopulmonary infections, because of the combined immunodeficiency. 

Individuals with NBS require the same types of care as those with other DNA breakage syndromes. Immunoglobulin (Ig) replacement therapy can help with the recurrent infections. Health maintenance and cancer surveillance are critically important, as is aggressive management of infections and related problems.

Read the latest research

Learn more about combined immune deficiencies.

This page contains general medical and/or legal information that cannot be applied safely to any individual case. Medical and/or legal knowledge and practice can change rapidly. Therefore, this page should not be used as a substitute for professional medical and/or legal advice.

Adapted from the IDF Patient & Family Handbook for Primary Immunodeficiency Diseases, Sixth Edition 
Copyright ©2019 by Immune Deficiency Foundation, USA