Examples are vitamin D-resistant disorders (e.g., vitamin D-resistant rickets; genetic abnormalities of CYP enzymes), hypoparathyroidism, genetic and acquired hypophosphataemic osteomalacia, renal osteodystrophy, migraine, psoriasis, malabsorption, obesity, osteomalacia secondary to hepatic impairment, etc. This evidence concerns the gene PPIG and hypoparathyroidism.