MedGen

An anomaly of the U wave of the electrocardiogram (EKG). The U wave is a small (0.5 mm) deflection immediately following the T wave, usually in the same direction as the T wave. It is best seen in leads V2 and V3. [from HPO]

Nijmegen breakage syndrome (NBS) is characterized by progressive microcephaly, early growth deficiency that improves with age, recurrent respiratory infections, an increased risk for malignancy (primarily lymphoma), and premature ovarian failure in females. Developmental milestones are attained at the usual time during the first year; however, borderline delays in development and hyperactivity may be observed in early childhood. Intellectual abilities tend to decline over time. Recurrent pneumonia and bronchitis may result in respiratory failure and early death. Other reported malignancies include solid tumors (e.g., medulloblastoma, glioma, rhabdomyosarcoma). [from GeneReviews]