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- Lorentzon, Mattias, 1970, et al.
(författare)
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The COMT val158met polymorphism is associated with peak BMD in men.
- 2004
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Ingår i: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. - 0884-0431. ; 19:12, s. 2005-11
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Tidskriftsartikel (refereegranskat)abstract
- The associations between the functional val158met polymorphism of the estrogen-degrading COMT enzyme and skeletal properties in young men were investigated. BMD was associated with COMT genotype. INTRODUCTION: Peak BMD is an important predictor of future risk of osteoporosis, and it is to a large extent determined by genetic factors. Estrogens are involved in the accretion of bone mass during puberty. Catechol-O-methyltransferase (COMT) is involved in the degradation of estrogens. There is a functional polymorphism in the COMT gene (val158met), resulting in a 60-75% difference in enzyme activity between the val (high activity [H]) and met (low activity [L]) variants. The aim of this cross-sectional study was to investigate the associations between this polymorphism and peak BMD in young men. MATERIALS AND METHODS: A total of 458 healthy men (mean age, 19 +/- 0.6 years) were genotyped and classified as COMT(LL), COMT(HL), or COMT(HH). Areal BMD (aBMD) was measured by DXA. Cortical and trabecular volumetric BMD (vBMD) were measured by pQCT. The associations between COMT genotype and skeletal phenotypes were determined. RESULTS AND CONCLUSIONS: Regression models using physical activity, height, weight, age, and COMT genotype as covariates showed that COMT genotype was an independent predictor of aBMD in the total body and in all femur locations investigated, but not in the spine. The values for COMT(HL) and COMT(HH) were very similar, and therefore, they were pooled into one group. aBMD at Ward's triangle, trochanter, and total femur were 4.9%, 4.5%, and 3.7% lower, respectively, in the COMT(LL) than in the COMT(HL/HH) group (p < 0.01). pQCT analyses showed that COMT genotype was an independent predictor of trabecular vBMD of the tibia, radius, and fibula. Trabecular vBMD of the radius and fibula in COMT(LL) was 5.3% and 7.4% lower, respectively, than that of the combined COMT(HL/HH) group. COMT genotype was associated with cortical vBMD but not with cortical cross-sectional area in the tibia. These findings show that the COMT polymorphism is associated with BMD in young adult men.
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| 2. |
- Nordström, Anna, 1973-, et al.
(författare)
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Interleukin-6 promoter polymorphism is associated with bone quality assessed by calcaneus ultrasound and previous fractures in a cohort of 75-year-old women.
- 2004
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Ingår i: Osteoporosis international. - : Springer Science and Business Media LLC. - 0937-941X .- 1433-2965. ; 15:10, s. 820-6
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Tidskriftsartikel (refereegranskat)abstract
- Interleukin 6 (IL-6) is a multifunctional cytokine and a potent stimulator of bone resorption and has been implicated in the pathogenesis of osteoporosis in postmenopausal women. The aim of this study was to investigate if a functional IL-6 promoter polymorphism (-174) was related to bone mass and fractures in a cohort consisting of 964 postmenopausal Caucasian women aged 75 years. Bone mineral density (BMD; g/cm2) of the femoral neck, lumbar spine and total body was measured using dual energy X-ray absorptiometry (DXA). Quantitative ultrasound (QUS) was also measured in the calcaneus and quantified as speed of sound (SOS; m/s), broadband ultrasound attenuation (BUA; dB/MHz), and stiffness index (SI). IL-6 genotypes was determined by restriction fragment length polymorphism (RFLP) using the restriction enzyme NlaIII. The frequencies of the different IL-6 genotypes were 27.5% (GG), 47.9% (GC), 24.6% (CC). The IL-6 polymorphism (presence of G) was independently related to a lower stiffness (beta=-0.07; P=0.03) and BUA (beta=-0.08; P=0.02), but not to BMD at any site measured by DXA. In the cohort, 420 subjects (44%) reported at least one fracture during their lifetime, and 349 (36%) reported at least one fracture after the age of 50. Using binary logistic regression, the IL-6 polymorphism (presence of G) was significantly related to an increased risk of a previous fracture during life (odds ratio 1.46, 95% CI 1.08-1.97) and to an increased risk of a fracture occurring after 50 years of age (odds ratio 1.37, 95% CI 1.004-1.88). The risk was further increased for fractures grouped as osteoporotic fractures (odds ratio 1.67, 95% CI 1.14-2.45), including forearm fractures (odds ratio 1.59, 95% CI 1.05-2.40). In conclusion, presence of G allele in the IL-6 promoter polymorphism at position -174 is independently related to previous fractures in postmenopausal women. This association may be related primarily to an altered bone quality identified by QUS and not a lower bone mass. This is also the first demonstration of association of IL-6 gene polymorphism to calcaneal QUS.
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