Diagnostic exome sequencing identifies haploinsufficiency and chromosome 20 uniparental disomy in a patient with developmental anomalies.

Clinical diagnostic exome sequencing (DES) is currently infrequently used for detecting uniparental disomy (UPD). We present a patient with a dual diagnosis of haploinsufficiency as well as UPD of chromosome 20, both identified through DES. We therefore recommend routine UPD analysis during DES to identify this genetic aberration.