NDN and Prader-Willi syndrome: Nevertheless, the Del Ndn-Magel2 mice with a deletion including both genes is more relevant from which to study PWS from a genetic and transcriptional point of view since in this mouse model both genes are deleted without the overexpression of Magel2 or Necdin that could occur in the single KO mice for Magel2- or Necdin-KO mice.