The human MAGEL2 gene and its mouse homologue are paternally expressed andmapped to the Prader-Willi region

Prader-Willi syndrome (PWS) is a complex neurogenetic disorder, The phenoty pe is likely to be a contiguous gene syndrome involving genes which are pat ernally expressed only, located in the human 15q11-q13 region. Four mouse m odels of PWS have been reported but these do not definitively allow the del ineation of the critical region and the associated genes involved in the ae tiology of PWS, Moreover, targeted mutagenesis of mouse homologues of the h uman candidate PWS genes does not appear to result in any of the features o f PWS, Therefore, the isolation of new genes in this region remains crucial for a better understanding of the molecular basis of PWS. In this manuscri pt, we report the characterization of MAGEL2 and its mouse homologue Magel2 , These are located in the human 15q11-q13 and mouse 7C regions, in close p roximity to NDN/Ndn. By northern blot analysis we did not detect any expres sion of MAGEL2/Magel2 but by RT-PCR analysis, specific expression was detec ted in fetal and adult brain and in placenta, Both genes are intronless wit h tandem direct repeat sequences contained within a CpG island in the 5'-un transcribed region. The transcripts encode putative proteins that are homol ogous to the MAGE proteins and NDN, Moreover, MAGEL2/Magel2 are expressed o nly from the paternal allele in brain, suggesting a potential role in the a etiology of PWS and its mouse model, respectively.