We have been investigating families with naturally occurring chromosomal breaks as a shortcut to localize disease genes. We present here a family with a history of cerebral hemorrhages and aortic ruptures, demonstrating that a chromosomal break truncates the Neurotrimin gene on chromosome 11 in this family. The family samples were gathered as a part of our recently launched National Registry of Reciprocal Balanced Translocations and Inversions in Finland (n=2575), and we believe that such a registry will continue to facilitate identification of risk factors for both monogenic and complex diseases. (By Teppo Varilo M.D., Ph.D., http://jmg.bmj.com/content/49/10/621 )