Bone Abstracts

Aim: Lean and bone mass have considerably high phenotypic and genetic correlations with a shared heritability estimate ranging between 30 and 40% in adults. A genome-wide association study (GWAS) on total body lean mass and a bivariate GWAS on lean mass and BMD were ran in a cohort of children to identify genes with pleiotropic effects on muscle mass and peak bone mass attainment.Methods: Subjects are part of the Generation R study, a prospective multiet...

C5aR is a membrane-associated receptor for C5a, a potent immune mediator generated after complement activation. C5aR expressed in tumor infiltrating immune cells creates a favorable microenvironment for tumor progression. However, the expression of C5aR by cancer cells and its contribution to their malignant phenotype is poorly understood. Immunohistochemical analysis revealed that high levels of C5aR in human lung tumors were associated with poor survival (P=0.005) a...

Sclerostin, encoded by the SOST gene, functions as an inhibitor of the Wnt pathway and thus it is an important regulator of bone homeostasis. The fact that osteoblasts, the only cells expressing SOST, lay buried deeply in the bone matrix, poses intrinsic difficulties to the study of the regulation of this gene. Since RUNX2 and SP7/OSX are two known regulators of the differentiation of cells of the osteoblastic lineage, the aim of this study was to determine t...

Objectives: Advanced or delayed physiological age may influence significantly health and disease processes. Physiological age can be estimated using several parameters including dental age (DA). Previous meta-analyses studying “Number of Teeth at 15 Months” (NT15M) and “Age at First Teeth Eruption” (AFTE) have identified 15 loci. We performed a genome-wide association study (GWAS) meta-analysis to identi...

Background/aim: X-linked hypophosphatemia (XLH) is a rare disease characterized by low phosphate level. Scientific evidence points to link between hypophosphatemia and obesity in general population. The aim of our longitudinal observational study was to investigate the prevalence of obesity and associated factors in a large cohort of children with XLH.Patients/methods: We selected 172 XLH-children of 5–20 years (113 girls/59 boys). Anthropometric pa...

see PP282....

Heritability of bone mineral density (BMD) varies at skeletal sites, possibly reflecting different relative contributions of environmental and genetic influences. To quantify shared genetic influences across different sites, we estimated the genetic correlation of BMD at the upper limb (UL), lower limb (LL), and skull (S) obtained from whole body DXA scans, using bivariate genome-wide complex trait analysis (GCTA). The study (n=9395) combined data from the Avon Longit...

Background: Lean and bone mass are heritable traits with high phenotypic correlation (rho=0.44), likely reflecting the underlying mechanical and biochemical interactions between tissues.Aim: Estimate the shared heritability (genetic correlation) of both traits in children and identify genetic determinants displaying pleiotropic effects on lean mass and bone mass accrual.Methods: Participants make part of two prospective po...

Background: Osteoporosis-pseudoglioma (OPPG) syndrome is an autosomal recessive disorder characterised by severe juvenile osteoporosis and congenital or infancy-onset visual loss. OPPG is caused by loss of function mutations in LDL receptor-related protein 5 (LRP5) gene. We present a 13-year-old child with a homozygous mutation in LRP5 and low bone mass but without visual loss.Presenting problem/clinical management: This child presented with multiple low...

Background: Genetic disorders of mineral metabolism causing nephrolithiasis and bone abnormalities are uncommon and have a varied clinical spectrum. Hypophosphataemic rickets with hypercalciuria (HHRH) is a rare autosomal-recessive condition, typically presenting with severe rickets and hypophosphataemia. Milder forms can present with hypercalciuria and nephrolithiasis without bone disease. The underlying pathophysiology is due to mutations in the SLC34A3 gene, which encodes t...