| 1. |
- Moayyeri, Alireza, et al.
(författare)
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Genetic determinants of heel bone properties : genome-wide association meta-analysis and replication in the GEFOS/GENOMOS consortium
- 2014
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Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 23:11, s. 3054-3068
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Tidskriftsartikel (refereegranskat)abstract
- Quantitative ultrasound of the heel captures heel bone properties that independently predict fracture risk and, with bone mineral density (BMD) assessed by X-ray (DXA), may be convenient alternatives for evaluating osteoporosis and fracture risk. We performed a meta-analysis of genome-wide association (GWA) studies to assess the genetic determinants of heel broadband ultrasound attenuation (BUA; n = 14 260), velocity of sound (VOS; n = 15 514) and BMD (n = 4566) in 13 discovery cohorts. Independent replication involved seven cohorts with GWA data (in silico n = 11 452) and new genotyping in 15 cohorts (de novo n = 24 902). In combined random effects, meta-analysis of the discovery and replication cohorts, nine single nucleotide polymorphisms (SNPs) had genome-wide significant (P < 5 x 10(-8)) associations with heel bone properties. Alongside SNPs within or near previously identified osteoporosis susceptibility genes including ESR1 (6q25.1: rs4869739, rs3020331, rs2982552), SPTBN1 (2p16.2: rs11898505), RSPO3 (6q22.33: rs7741021), WNT16 (7q31.31: rs2908007), DKK1 (10q21.1: rs7902708) and GPATCH1 (19q13.11: rs10416265), we identified a new locus on chromosome 11q14.2 (rs597319 close to TMEM135, a gene recently linked to osteoblastogenesis and longevity) significantly associated with both BUA and VOS (P < 8.23 x 10(-14)). In meta-analyses involving 25 cohorts with up to 14 985 fracture cases, six of 10 SNPs associated with heel bone properties at P < 5 x 10(-6) also had the expected direction of association with any fracture (P < 0.05), including three SNPs with P < 0.005: 6q22.33 (rs7741021), 7q31.31 (rs2908007) and 10q21.1 (rs7902708). In conclusion, this GWA study reveals the effect of several genes common to central DXA-derived BMD and heel ultrasound/DXA measures and points to a new genetic locus with potential implications for better understanding of osteoporosis pathophysiology.
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| 2. |
- Jiang, Jieying, et al.
(författare)
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Association of genetic variations in aromatase gene with serum estrogen and estrogen/testosterone ratio in Chinese elderly men.
- 2010
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Ingår i: Clinica chimica acta. - : Elsevier BV. - 1873-3492 .- 0009-8981. ; 411:1-2, s. 53-8
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Single nucleotide polymorphism (SNP) rs2470152 of the gene CYP19A1 is associated with serum estradiol (E2) levels in Caucasian men. However, it remains to be verified if rs2470152 is the sole determinant accounting for the association. We determined whether 2 CYP19A1 SNPs tagging different haploblocks (rs2470152 and rs2899470) are associated with sex steroid levels in Chinese men. METHOD: Serum sex steroid level including E2, estrone (E1) and testosterone (T), of 1402 Chinese men aged > or = 65 years were analyzed. Genotyping of the two CYP19A1 SNPs was performed using Tm-shift allele-specific PCR. RESULTS: SNP rs2899470 was significantly associated with serum E2, E1 levels and E2/T ratio (p<0.001). However, SNP rs2470152 was only modestly associated with E2/T ratio (p=0.023). Analysis of haplotype showed a significant association between C-G, T-T haplotype with serum E2/T ratio (p=0.019 and p=1 x 10(-5), respectively). Similarly, E2 levels was also associated the T-T and T-G haplotypes (p=1 x 10(-5)). CONCLUSION: The genetic variation of CYP19A1 was associated with circulating estrogen levels in Chinese elderly men. In addition, it revealed that haplotype of rs2899470 and rs2470152, rather than rs2899470 alone, was a better indicator for the serum E2/T ratio and E2 levels.
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| 3. |
- Meng, Jerry, et al.
(författare)
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Associations of estradiol and testosterone with serum phosphorus in older men : the Osteoporotic Fractures in Men study
- 2010
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Ingår i: Kidney International. - : Elsevier BV. - 0085-2538 .- 1523-1755. ; 78:4, s. 415-422
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Tidskriftsartikel (refereegranskat)abstract
- Postmenopausal women consistently have higher phosphorus levels than similarly aged men. As it is known that estradiol induces phosphaturia in rodents, we evaluated the cross-sectional association of sex hormones with serum phosphorus in 1346 community-living older men (mean age 76) of which 18% had moderate (stage 3) kidney disease. Using linear regression with serum phosphorus levels as the dependent variable, we found that for each 10 pg/ml higher total estradiol level there was a statistically significant 0.05 mg/dl lower serum phosphorus when adjusted for age, ethnicity, testosterone, sex hormone-binding globulin, calcium, estimated glomerular filtration rate, intact parathyroid hormone, 25(OH) vitamin D, bone mineral density, and alkaline phosphatase. These results were similar in individuals with or without chronic kidney disease. Serum testosterone concentrations were also statistically significantly associated with lower serum phosphorus levels. We confirmed these results in an independent sample of 2555 older men, wherein these associations were not attenuated when adjusted for fibroblast growth factor-23 levels. Hence, our study of community-living older men suggests that estradiol may directly or indirectly induce phosphaturia in humans. The mechanism responsible for the association of testosterone with serum phosphorus remains to be determined.
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| 4. |
- Jiang, Jieying, et al.
(författare)
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Association of SRD5A2 variants and serum androstane-3alpha,17beta-diol glucuronide concentration in Chinese elderly men.
- 2010
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Ingår i: Clinical chemistry. - : Oxford University Press (OUP). - 1530-8561 .- 0009-9147. ; 56:11, s. 1742-9
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Tidskriftsartikel (refereegranskat)abstract
- Results of recent studies have demonstrated that genetic variants of the enzyme steroid 5α reductase type II (SRD5A2) are associated with serum concentrations of major androgen metabolites such as conjugates of androstane-3α,17β-diol-glucuronide (3α-diol-G). However, this association was not consistently found among different ethnic groups. Thus, we aimed to determine whether the association with SRD5A2 genetic variations exists in a cohort of healthy Chinese elderly men, by examining 2 metabolite conjugates: androstane-3α,l7β-diol-3-glucuronide (3α-diol-3G) and androstane-3α,17β-diol-17-glucuronide (3α-diol-17G).
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| 5. |
- Orwoll, Eric S., et al.
(författare)
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Evidence for Geographical and Racial Variation in Serum Sex Steroid Levels in Older Men
- 2010
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 95:10, s. E151-E160
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Tidskriftsartikel (refereegranskat)abstract
- Background: Despite considerable racial and geographical differences in human phenotypes and in the incidence of diseases that may be associated with sex steroid action, there are few data concerning variation in sex steroid levels among populations. We designed an international study to determine the degree to which geography and race influence sex steroid levels in older men. Methods: Using mass spectrometry, concentrations of serum androgens, estrogens, and sex steroid precursors/metabolites were measured in 5003 older men from five countries. SHBG levels were assessed using radioimmunoassay. Results: There was substantial geographical variation in the levels of sex steroids, precursors, and metabolites, as well as SHBG. For instance, Asian men in Hong Kong and Japan, but not in the United States, had levels of total testosterone approximately 20% higher than in other groups. Even greater variation was present in levels of estradiol, SHBG, and dihydrotestosterone. Group differences in body mass index did not explain most geographical differences. In addition, body mass index-independent racial differences were present; Black men had higher levels of estrogens (estradiol, estrone), and Asian men had lower levels of glucuronidated androgen metabolites. Conclusions: On a global scale, there are important geographical and racial differences in the concentrations of serum sex steroids and SHBG in older men.
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