Nijmegen breakage syndrome is a condition characterized by short stature, an unusually small head size (microcephaly), distinctive facial features, recurrent respiratory tract infections, an increased risk of cancer, intellectual disability, and other health problems.

Mutations in the NBN gene cause Nijmegen breakage syndrome. The NBN gene provides instructions for making a protein called nibrin. This protein is involved in several critical cellular functions, including the repair of damaged DNA. DNA can be damaged by agents such as toxic chemicals or radiation. Breaks in DNA strands also occur naturally when chromosomes exchange genetic material in preparation for cell division. Repairing DNA prevents cells from accumulating genetic damage that can cause them to die or to divide uncontrollably. The nibrin protein helps maintain the stability of a cell's genetic information through its roles in repairing damaged DNA and regulating cell division.

The exact prevalence of Nijmegen breakage syndrome is unknown. This condition is estimated to affect one in 100,000 newborns worldwide, but is thought to be most common in the Slavic populations of Eastern Europe.

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.

Published Date: May 01, 2017
Published By: National Institutes of Health