Lack of association of superoxide dismutase I/D variant with osteopenia/osteoporosis in Turkish postmenopausal women

Abstract

Background Osteoporosis (OP) is a common systemic, metabolic bone disease that affects 40% of postmenopausal women. Oxidative stress (OS) ìs caused by reactive oxygen species (ROS), inhibits osteoblast differentiation and causes apoptosis in osteoblastic cells. Superoxide dismutase (SOD) reduces OS by playing a role in the reduction and defense of intracellular ROS. Therefore, the purpose of this study was to investigate the relationship between osteopenia/OP and the SOD1 50-bp insertion/deletion (I/D) variant in Turkish postmenopausal women. Methods A total of 180 women participated in this study includḭng 89 osteopenia/OP postmenopausal women and 91 healthy postmenopausal women. T-score > −1 standard deviation (SD) defined normal bone mass, T-score between −1 and −2.5 SD defined osteopenia, T-score ≥ −2.5 SD was defined as OP. DNA was extracted from all subjects and the SOD1 I/D variant genotyped by PCR. The results of the analyses were evaluated for statistical significance. Results The mean age of 89 osteopenia/OP patients aged 45 to 74 was 58.57 ± 6.57. There was no D/D homozygous genotype in the patient and control groups. The prevalence of genotypes of I/I, and I/D, profiles for the SOD1 I/D variant were 76.4%, and 23.6% respectively, in patients, and 72.5%, and 27.5% respectively, in the control group. When the patient group and control group were compared, the SOD1 I/D genotype distribution and allele frequencies did not show a significant difference between the groups (p > 0.05). Conclusion Our results showed that the SOD1 I/D variant may not be considered a determining factor in the development of osteopenia/OP in a Turkish population sample. However, ethnic differences, gene-gene, and gene-environment interactions should not be ignored.