PLEC is expressed in various tissues, including muscles and fibroblasts (Consortium, 2015), and PLEC deficiency causes epidermolysis bullosa simplex with muscular dystrophy (OMIM 226670) (Smith et al., 1996), in which osteoporosis frequently develops (Chen et al., 2019). Here, PLEC is linked to hyperinsulinemic hypoglycemia, familial, 4.