IGF-1 polymorphisms modulate the susceptibility to osteonecrosis of the femoral head among Chinese Han population

The study was performed to investigate the genetic associations of IGF-1 polymorphisms rs35767, rs5742714, and rs972936 with susceptibility to osteonecrosis of the femoral head (ONFH) among Chinese Han population. Totally, 101 ONFH patients and 128 healthy controls were enrolled. Hardy-Weinberg equilibrium (HWE) was detected with chi-square test in control group. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated to estimate the relationship between IGF-1 polymorphisms and ONFH risk. Besides, hyplotype analysis was performed to examine linkage disequilibrium between the studied polymorphisms. Genotype AA and allele A of polymorphism rs35767 were more frequent in control group, and offered protection for ONFH onset (AA: OR=0.382, 95% CI=0.158-0.923; A: OR=0.650, 95% CI=0.442-0.956). Furthermore, the negative relationship was also observed between ONFH risk and polymorphism rs5742714 under the comparisons CG vs CC, and G vs C (OR=0.395, 95% CI=0.199-0.787; OR=0.346, 95% CI=0.191-0.627). While the polymorphism rs972936 significantly enhanced the disease risk (CT vs CC: OR=2.434, 95% CI=1.184-5.003; TT vs CC: OR=2.497, 95% CI=1.040-5.990). Furthermore, haplotype analysis demonstrated that C-T (rs5742714-rs972936) could increase ONFH risk (OR=2.177, 95% CI=1.444-3.283), while G-T might be a protective factor for ONFH (OR=0.472, 95% CI=0.254-0.878). IGF-1 polymorphisms rs35767, rs5742714, and rs972936 show significant association with ONFH risk.