Thus, patients with mutations in ZFP57 (which is involved in the establishment and maintenance of genomic imprinting) presenting with prenatal growth failure and transient neonatal diabetes mellitus (TNDM, OMIM 601410) showed loss of maternal methylation at the PLAGL1 DMR and variable loss of maternal methylation at GRB10, PEG3, NESPAS and MEST[16]. The gene discussed is GNAS-AS1; the disease is transient neonatal diabetes mellitus.