Exome sequencing identifies a cryptic chromosome translocation in a family decades after clinical diagnosis of Cornelia de Lange: Case report.

Clinical genetic evaluations are defined by the knowledge and technology available at the time they occur. In the modern era, microarray and exome sequencing are first line tests for clinical geneticists; however, beginning in the late 1970s and continuing until the turn of the past century, a standard genetic evaluation consisted, in many cases, of an examination by a dysmorphologist as well as a conventional karyotype. In general, once a genetic diagnosis is established, it does not get revisited as more advanced methods become available. Clearly, there will be instances in which new technology can modify or change a prior diagnosis. We present a family in which the recent birth of a baby resulted in the establishment of a cytogenetic diagnosis of a different family member whose initial evaluation and clinical diagnosis had occurred three decades earlier. The new genomic findings have profound implications for other family members, and in addition provided the family with a sense of closure.