Because IGF‐1 is the key effector of growth hormones and inhibits hair cell apoptosis [34], we speculate that chronic suppression of IGF‐1 signalling due to reduced blood insulin levels can contribute to growth failure and hearing impairment in PFIC1 patients [5] and Atp8b1 mutant mice [6, 21]. This evidence concerns the gene INS and Hearing impairment.