EIF2A and hyperinsulinemic hypoglycemia, familial, 4: In addition to ER stress via PERK-mediated eIF2α activation, other conditions such as viral infection (PKR), amino acid starvation (general control non-derepressible-2), and heme deficiency (heme-regulated inhibitor kinase) also phosphorylates eIF2α [65–69], thus, examining all the conditions in the male and female labyrinth and junctional zones were beyond the scope of the current study.