Denosumab given subcutaneously twice yearly for 36 months was associated with a reduction in the risk of vertebral, nonvertebral, and hip fractures in women with osteoporosis. (ClinicalTrials.gov number, NCT00089791.)

We have previously reported suggestive linkage of type 2 diabetes mellitus to chromosome 10q. We genotyped 228 microsatellite markers in Icelandic individuals with type 2 diabetes and controls throughout a 10.5-Mb interval on 10q. A microsatellite, DG10S478, within intron 3 of the transcription factor 7-like 2 gene (TCF7L2; formerly TCF4) was associated with type 2 diabetes (P = 2.1 x 10(-9)). This was replicated in a Danish cohort (P = 4.8 x 10(-3)) and in a US cohort (P = 3.3 x 10(-9)). Compared with non-carriers, heterozygous and homozygous carriers of the at-risk alleles (38% and 7% of the population, respectively) have relative risks of 1.45 and 2.41. This corresponds to a population attributable risk of 21%. The TCF7L2 gene product is a high mobility group box-containing transcription factor previously implicated in blood glucose homeostasis. It is thought to act through regulation of proglucagon gene expression in enteroendocrine cells via the Wnt signaling pathway.

Bone mineral density (BMD) is the most important predictor of fracture risk. We performed the largest meta-analysis to date on lumbar spine and femoral neck BMD, including 17 genome-wide association studies and 32,961 individuals of European and East Asian ancestry. We tested the top-associated BMD markers for replication in 50,933 independent subjects and for risk of low-trauma fracture in 31,016 cases and 102,444 controls. We identified 56 loci (32 novel)associated with BMD atgenome-wide significant level (P<5×10−8). Several of these factors cluster within the RANK-RANKL-OPG, mesenchymal-stem-cell differentiation, endochondral ossification and the Wnt signalling pathways. However, we also discovered loci containing genes not known to play a role in bone biology. Fourteen BMD loci were also associated with fracture risk (P<5×10−4, Bonferroni corrected), of which six reached P<5×10−8 including: 18p11.21 (C18orf19), 7q21.3 (SLC25A13), 11q13.2 (LRP5), 4q22.1 (MEPE), 2p16.2 (SPTBN1) and 10q21.1 (DKK1). These findings shed light on the genetic architecture and pathophysiological mechanisms underlying BMD variation and fracture susceptibility.

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The models developed provide the basis for the integrated use of validated clinical risk factors in men and women to aid in fracture risk prediction.

A variant in CDKAL1 influences insulin response and risk of type 2 diabetes Steinthorsdottir, V.; Thorleifsson, G.; Reynisdottir, I.; Benediktsson, R.; Jonsdottir, T.; Walters, G.B.; Styrkarsdottir, U.; Gretarsdottir, S.; Emilsson, V.; Ghosh, S.

Oral daily (2.5 mg) and intermittent ibandronate (between-dose interval of >2 months), delivering a similar cumulative exposure, were evaluated in 2946 osteoporotic women with prevalent vertebral fracture. Significant reduction in incident vertebral fracture risk by 62% and 50%, respectively, was shown after 3 years. This is the first study to prospectively show antifracture efficacy for the intermittent administration of a bisphosphonate. Introduction:Bisphosphonates are important therapeutics in postmenopausal osteoporosis. However, they are currently associated with stringent dosing instructions that may impair patient compliance and hence therapeutic efficacy. Less frequent, intermittent administration may help to overcome these deficiencies. This study assessed the efficacy and safety of oral ibandronate administered either daily or intermittently with a dose-free interval of Ͼ2 months. Materials and Methods:This randomized, double-blind, placebo-controlled, parallel-group study enrolled 2946 postmenopausal women with a BMD T score Յ Ϫ2.0 at the lumbar spine in at least one vertebra (L 1 -L 4 ) and one to four prevalent vertebral fractures (T 4 -L 4 ). Patients received placebo or oral ibandronate administered either daily (2.5 mg) or intermittently (20 mg every other day for 12 doses every 3 months). Results and Conclusions: After 3 years, the rate of new vertebral fractures was significantly reduced in patients receiving oral daily (4.7%) and intermittent ibandronate (4.9%), relative to placebo (9.6%). Thus, daily and intermittent oral ibandronate significantly reduced the risk of new morphometric vertebral fractures by 62% (p ϭ 0.0001) and 50% (p ϭ 0.0006), respectively, versus placebo. Both treatment groups also produced a statistically significant relative risk reduction in clinical vertebral fractures (49% and 48% for daily and intermittent ibandronate, respectively). Significant and progressive increases in lumbar spine (6.5%, 5.7%, and 1.3% for daily ibandronate, intermittent ibandronate, and placebo, respectively, at 3 years) and hip BMD, normalization of bone turnover, and significantly less height loss than in the placebo group were also observed for both ibandronate regimens. The overall population was at low risk for osteoporotic fractures. Consequently, the incidence of nonvertebral fractures was similar between the ibandronate and placebo groups after 3 years (9.1%, 8.9%, and 8.2% in the daily, intermittent, and placebo groups, respectively; difference between arms not significant). However, findings from a posthoc analysis showed that the daily regimen reduces the risk of nonvertebral fractures (69%; p ϭ 0.012) in a higher-risk subgroup (femoral neck BMD T score Ͻ Ϫ3.0). In addition, oral ibandronate was well tolerated. Oral ibandronate, whether administered daily or intermittently with an extended between-dose interval of Ͼ2 months, is highly effective in reducing the incidence of osteoporotic fractures in postmenopausal women. This is the first time that significant fracture effi...

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