Once reported by the national screening center, the diagnosis of CH should be confirmed by evaluating the thyroid hormone profile of thyroid stimulating hormone (TSH), free Thyroxine (fT4) and free triiodothyronine (fT3), thyroglobulin dosage and radiological evaluation by ultrasound and/or Tc99 or I121 scintiscan. The gene discussed is TG; the disease is cyclic hematopoiesis.