Copy number variants, aneuploidies, and human disease.

In the perinatal setting, chromosome imbalances cause a range of clinically significant disorders and increase the risk for other particular phenotypes. As technologies have improved to detect increasingly smaller deletions and duplications, collectively referred to as copy number variants (CNVs), clinicians are learning the significant role that these types of genomic variants play in human disease and their high frequency in ∼ 1% of all pregnancies. This article highlights key aspects of CNV detection and interpretation used during the course of clinical care in the prenatal and neonatal periods. Early diagnosis and accurate interpretation are important for targeted clinical management.