Prenatal detection of de novo duplication of the short arm of chromosome 18 confirmed by fluorescence in situ hybridization (FISH).

We present a patient with developmental delay, minor anomalies, and duplication 18p confirmed by fluorescence in situ hybridization with whole chromosome 18 painting probe (Oncor p5218). Our observation confirms the findings of other investigators that duplication 18p is not associated with major malformations.