Other medical concerns for people with inherited NBN mutations
Inheriting an NBN mutation from both parents can cause Nijmegen breakage syndrome. Nijmegen breakage syndrome affects about one in 100,000 newborns worldwide, but is thought to be most common in people from Eastern Europe of Slavic ethnicity.
People with Nijmegen breakage syndrome have short stature, an unusually small head size (microcephaly), distinctive facial features, recurrent respiratory infections, intellectual disability, and other health problems. People with Nijmegen breakage syndrome also have an increased risk of developing cancer, most commonly a cancer of the immune system called non-Hodgkin lymphoma. About half of people with Nijmegen breakage syndrome develop non-Hodgkin lymphoma, usually before age 15. Other cancers seen in people with Nijmegen breakage syndrome include brain tumors such as medulloblastoma and glioma, and a cancer of muscle tissue called rhabdomyosarcoma. People with Nijmegen breakage syndrome are 50 times more likely to develop cancer than people without this syndrome.
Couples where one partner has a known NBN mutation may wish to speak with a genetic counselor about testing the other partner prior to having children.