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.