Neurological features and long-term follow-up in 15q11.2-13.1 duplication

Various rearrangements occurring in the 15q11-q13 region have been reported in association with epilepsy. Deletions are the most frequent and are associated with Angelman or Prader–Willi syndrome. Duplications feature complex phenotypes including developmental delay, autistic-like behaviour and seizures. Among these, trisomy has been described as a milder phenotype compared to tetrasomy, but reports are rare and the phenotype is not yet defined. Here we report two adult cases with a 15q11.2-13.1 duplication showing a complex and similar epileptic phenotype.