Radiation Oncology/Cancer Syndromes/Nijmegen Breakage Syndrome

Nijmegen Breakage Syndrome


 * Gene Reviews link
 * Online Mendelian Inheritance in Man
 * DNA Repair chapter


 * Absence of nibrin protein (NBS1 gene), part of MRN complex involved in DNA double-strand break recognition and repair
 * Short stature, progressive microcephaly with loss of cognitive skills, premature ovarian failure in females, recurrent sinopulmonary infections, and an increased risk for cancer
 * Historically considered a variant of A-T, until separate genes demonstrated
 * 70 individuals reported to-date
 * Cancer risk: 35% malignancy (25/70)
 * Lymphoma 90% (22/25)
 * Sensitivity to ionizing radiation