It is noteworthy that few observations about uncertainty in genetic screening and testing are unique to genomic research or practice. One exception may be found in the possibility that expansion of newborn screening may identify maternal disease [B-7, Buchbinder]. However, genomics often simply makes more ambiguous information more readily available, thus highlighting the need for expert professional understanding and the professional time and talent to undertake the necessary education and counseling for patients and families. For example, variants of unknown significance (VUS) have long presented very similar challenges when they are identified in imaging studies. Today, VUS are frequently seen in microarray testing, even when it is employed in the hope of making a more definitive identification of as-yet-unexplained anomalies [B-7, Reiff; E-7, Bernhardt]. Another type of VUS that is unique to genomics is copy number variants (CNVs), which are now detected with some frequency in patients with autism spectrum disorder through array comparative genomic hybridization [B-7, Shutske]. While, as noted above, this is becoming routine in clinical care, newly identified CNVs do not provide definitive confirmation of etiology; this
