Vitamin D deficiency (25(OH)D < 50 nmol/L was found in 84.6% of females and 67.5% of males (P < 0.008) and secondary hyperparathyroidism (PTH > 6.8 pmol/L) in 39.4% and 25.3%, respectively (P = 0.028). The gene discussed is PTH; the disease is vitamin D deficiency.