Supplementary Material for: Associations of Serum Osteocalcin and Polymorphisms of the Osteocalcin Gene with Bone Mineral Density in Postmenopausal and Elderly Chinese Women

<p><b><i>Background:</i></b> The aims of this study were: (1) to evaluate the association of serum osteocalcin with bone mineral density (BMD) and markers of bone metabolism in postmenopausal and elderly Chinese women, and (2) to observe the relationships of single-nucleotide polymorphisms (SNPs) in and around the <i>osteocalcin</i> gene with osteocalcin and BMD. <b><i>Methods:</i></b> A cross-sectional study was conducted with 725 postmenopausal Chinese women. Five SNPs (rs1543294, rs1800247, rs759330, rs2842880, and rs933489) of the <i>osteocalcin</i> gene were genotyped. Serum osteocalcin and intact parathyroid hormone (PTH), 25-hydroxyvitamin D [25(OH)D], and type I collagen containing cross-linked C-telopeptide (β-CTX) were measured. The BMD of the lumbar spine and proximal femur was measured by dual-energy X-ray absorptiometry. <b><i>Results:</i></b> Osteocalcin was positively correlated with serum phosphorus (<i>p</i> = 0.001), alkaline phosphatase (ALP; <i>p</i> < 0.001), PTH (<i>p</i> = 0.002) and β-CTX (<i>p</i> < 0.001), and negatively correlated with BMD at the lumbar spine (<i>p</i> < 0.001) and total hip (<i>p</i> = 0.002). No significant association was obtained between the SNPs, haplotypes of the <i>osteocalcin</i> gene, and BMD or osteocalcin. <b><i>Conclusion:</i></b> Our results suggest that osteocalcin was positively correlated with serum phosphorus, ALP, PTH, and β-CTX, but negatively correlated with BMD at the lumbar spine and total hip. Common genetic variants of the <i>osteocalcin</i> gene may not be a major contributor to variations in serum osteocalcin or BMD in postmenopausal and elderly Chinese women.</p>