EIF2AK2 and obesity due to melanocortin 4 receptor deficiency: Following 10 weeks of a HFD, PKR KO mice had a moderately exacerbated obesity phenotype compared with their WT counterparts (fat mass=17.9±0.9 g versus 13.1±2.2 g; P<0.001; for PKR KO, n=7; and WT, n=8, respectively).