spine, femoral neck and total hip were 0.565, 0.702 and 0.693, respectively. Relationship between the BMD and the TFM and TLM in young men As shown in Table 2, Pearson’s correlation analyses confirmed that both the TFM and TLM were positively correlated with the BMD, with correlations ranging from 0.198 to 0.508 for the lumbar spine, femoral neck and total hip BMD. According to the Pearson’s coefficient (r), the TLM was more strongly related to the BMD at a given site. To determine the relative contributions of the TLM and TFM to the BMD, we constructed multiple regression models, which were simultaneously adjusted for age and height. Both the TLM and TFM were positively correlated Table 2 Pearson’s correlation coefficient (r) of the BMD with the TFM and TLM Lumbar spine Femoral neck Total hip BMD BMD (g cm–2) BMD (g cm–2) (g cm–2) F F 0.639 (0.000) 0.719 (0.000) 0.243 (0.000) 0.389 (0.000) F F F F 0.922 (0.000) 0.198 (0.000) 0.470 (0.000) F F F F F F 0.242 (0.000) 0.508 (0.000) Abbreviations: BMD, bone mineral density; TFM, total fat mass; TLM, total lean mass. Statistical significance is indicated in parentheses with the relevant P-values. Table 3 Multivariate regression analysis of the BMD against body composition components Total lean mass Total fat mass b 0.010** 0.012** 0.012** R2 0.149 0.210 0.249 b 0.005** 0.004** 0.005** Abbreviations: BMD, bone mineral density; TFM, total fat mass; TLM, total lean mass. Models were adjusted for age and height. **Po0.001. Table 4 Information on the ALOX12 SNPs analyzed in this study Variation Lumbar spine BMD (g cm–2) Femoral neck BMD (g cm–2) Total hip BMD (g cm–2) Total fat mass (kg) Total lean mass (kg) BMD Lumbar spine Femoral neck Total hip SNP rs2073438 rs2292350 rs312470 rs434473 rs312462 TFM (kg) F F F F F F F F 0.367 (0.000) TLM (kg) F F F F F F F F F F R2 0.056 0.051 0.068 A4G A4G A4G A4G G4A ALOX12 polymorphisms are associated with fat mass in men W-J Xiao et al with the BMD, whereas the TLM had a significantly greater effect on the BMD than the TFM per kilogram of tissue mass (Table 3). SNP genotyping and LD Six SNPs in the ALOX12 gene were genotyped; rs1235805 was excluded from further analysis because of the existence of homologous gene sequences, and too many families failed to pass the Mendelian inheritance check. The remaining five SNPs had a minor allele frequency of at least 0.15 and were in Hardy–Weinberg equilibrium (Table 4). To gain insight into the pattern of LD between alleles at polymorphic loci, pairwise disequilibria measures (D) were calculated (Figure 1). We found that each of these SNPs was in strong LD (D40.80), and one block with high LD was identified. We inferred that 19 different haplotypes were present in our population using a likelihood method based on PHASE. The most common haplotype (AGAGG) had a frequency of 31.8%, and four haplotypes (AGAGG, GAAAG, 381 Figure 1 LD patterns for the ALOX12 gene. The increasing degree of the darkness of the cells from white to black represents the increasing strength of the LD. The values in the cells are the pairwise degree of LD indicated by D 100 when Do1. Physical position Location and function Allele change HWE P-value MAF in Europeana MAF in Asiana MAF in this study 6 840 800 6 842 396 6 842 903 6 845 658 6 854 376 Intron 1 Intron 2 Intron 4 Exon 8 (Asn322Ser) Exon 14 (Leu634Leu) 0.43 0.98 0.57 0.44 0.24 0.308 0.645 0.045 0.467 0.133 0.333 0.263 0.256 0.444 0.111 0.353 0.338 0.159 0.494 0.151 Abbreviations: HWE, Hardy–Weinberg equilibrium; MAF, minor allele frequency; SNP, single-nucleotide polymorphism. aAccording to public information available in the dbSNP (http://www.ncbi.nlm.nih.gov) and the HapMap (http://www.Hapmap.org) databases. International Journal of Obesity