Biological tests showed normal corrected calcium levels at 2.29 mmol/L, phosphatemia at 0.67mmol/L, calcemia/phosphatemia ratio is 3,4, elevated PTH at 970 pg/L (64 times the normal level), vitamin D deficiency with a serum 25‐(OH)‐D level of 20 ng/mL, normal serum protein electrophoresis, normal complete blood count, negative CRP, ESR at 17 mm, and creatinine at 70 μmol/L. The gene discussed is PTH; the disease is vitamin D deficiency.