Numerous disease symptoms in PWS and AS cases, irrespective of the involvement of the same segment, lie in the fact that PWS is caused by the deletion of specific paternally expressed genes like MAGEL2, MKRN3, PWRN1, NDN, C15orf 2, SNURF-SNRPN, and other snoRNA genes. The gene discussed is PWRN1; the disease is Prader-Willi syndrome.