HD patients manifested lower segmental and total BMD values in comparison with age-matched healthy controls (Z-score: -0.17 ± 1.12) due to significantly higher levels of P (4.04 ± 1.33 vs. 3.39 ± 0.51 mg/dl, p<0.001), PTH (538.17 ± 363.99 vs. 48.86 ± 19.64 ng/L, p<0.0001), and OC (50.39 ± 34.91 vs. 16.32 ± 5.37 μg/L, p<0.0001). The gene discussed is BGLAP; the disease is Huntington disease.