Recent work suggests that defects in prohormone processing may underlie the appetitive phenotype in PWS, with SNORD116 deficiency linked to decreased expression of PCSK1 and its associated regulator NHLH2 in patient-derived iPSCs as well as across several tissues in Snord116+/–P mice (24). This evidence concerns the gene PCSK1 and Prader-Willi syndrome.