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.

Communicated by Stylianos E. AntonarakisHbVar (http://globin.bx.psu.edu/hbvar) is a locus-specific database (LSDB) developed in 2001 by a multi-center academic effort to provide timely information on the genomic sequence changes leading to hemoglobin variants and all types of thalassemia and hemoglobinopathies. Database records include extensive phenotypic descriptions, biochemical and hematological effects, associated pathology, and ethnic occurrence, accompanied by mutation frequencies and references. In addition to the regular updates to entries, we report significant advances and updates, which can be useful not only for HbVar users but also for other LSDB development and curation in general. The query page provides more functionality but in a simpler, more user-friendly format and known single nucleotide polymorphisms in the human α-and β-globin loci are provided automatically. Populationspecific β-thalassemia mutation frequencies for 31 population groups have been added and/or modified and the previously reported δ-and α-thalassemia mutation frequency data from 10 population groups have also been incorporated. In addition, an independent flat-file database, named XPRbase (http://www.goldenhelix.org/xprbase), has been developed and linked to the main HbVar web page to provide a succinct listing of 51 experimental protocols available for globin gene mutation screening. These updates significantly augment the database profile and quality of information provided, which should increase the already high impact of the HbVar database, while its combination with the UCSC powerful genome browser and the ITHANET web portal paves the way for drawing connections of clinical importance, that is from genome to function to phenotype.

We developed a series of interrelated locus-specific databases to store all published and unpublished genetic variation related to these disorders, and then implemented microattribution to encourage submission of unpublished observations of genetic variation to these public repositories 1. A total of 1,941 unique genetic variants in 37 genes, encoding globins (HBA2, HBA1, HBG2, HBG1, HBD, HBB) and other erythroid proteins (ALOX5AP, AQP9, ARG2, ASS1, ATRX, BCL11A, CNTNAP2, CSNK2A1, EPAS1, ERCC2, FLT1, GATA1, GPM6B, HAO2, HBS1L, KDR, KL, KLF1, MAP2K1, MAP3K5, MAP3K7, MYB, NOS1, NOS2, NOS3, NOX3, NUP133, PDE7B, SMAD3, SMAD6, and TOX) are currently documented in these databases with reciprocal attribution of microcitations to data contributors. Our project provides the first example of implementing microattribution to incentivise submission of all known genetic variation in a defined system. It has demonstrably increased the reporting of human variants and now provides a comprehensive online resource for systematically describing human genetic variation in the globin genes and other genes contributing to hemoglobinopathies and thalassemias. The large repository of previously reported data, together with more recent data, acquired by microattribution, demonstrates how the comprehensive documentation of human variation will provide key insights into normal biological processes and how these are perturbed in human genetic disease. Using the microattribution process set out here, datasets which took decades to accumulate for the globin genes could be assembled rapidly for other genes and disease systems. The principles established here for the globin gene system will serve as a model for other systems and the analysis of other common and/or complex human genetic diseases.

Vascular endothelial growth factor (VEGF) is a potent mediator of angiogenesis which has multiple effects in lung development and physiology.