Maternal imprinting of the mouse Snrpn gene and conserved linkage homology with the human Prader-Willi syndrome region

Prader–Willi syndrome (PWS) is associated with paternal gene deficiencies in human chromosome 15q11–13, suggesting that PWS is caused by a deficiency in one or more maternally imprinted genes. We have now mapped a gene, Snrpn , encoding a brain–enriched small nuclear ribonucleoprotein (snRNP)–associated polypeptide SmN, to mouse chromosome 7 in a region of homology with human chromosome 15q11–13 and demonstrated that Snrpn is a maternally imprinted gene in mouse. These studies, in combination with the accompanying human mapping studies showing that SNRPN maps in the Prader–Willi critical region, identify SNRPN as a candidate gene involved in PWS and suggest that PWS may be caused, in part, by defects in mRNA processing.