Bone Abstracts

Autosomal Recessive Osteopetrosis (ARO) presents early in life with extreme sclerosis of the skeleton, reduction of bone marrow spaces, hepatosplenomegaly, cranial nerves compression and severe growth failure. ARO is often lethal and at present the only therapy is HSCT, which should be performed as soon as possible in order to obtain a major benefit. ARO is genetically heterogeneous and delays in clinical diagnosis sometimes occur, due to its rareness and to the presence of co...

Background: Hyperphosphatemic Familial Tumoral Calcinosis (HFTC) and Hyperphosphatemic Hyperostosis Syndrome (HHS) are two phenotypes of a disease associated with autosomal recessive mutations in FGF23, GALNT3 and KL, leading to reduced levels and clinical effects of fibroblast growth factor 23 (FGF23). We describe a consanguineous family with two affected individuals with HFTC and HHS caused by a novel homozygous mutation in GALNT3. We also...

Recessive osteogenesis imperfecta (OI) is caused by mutations in genes encoding proteins involved in post-translational interactions with type I collagen. A founder mutation in a new gene responsible for recessive OI has recently been reported in Bedouins from Israel and Saudi Arabia, who have a homozygous deletion of TMEM38B exon 4 and surrounding intronic sequence. TMEM38B encodes TRIC-B, an integral ER membrane monovalent cation channel involved in Ca...

Osteoporosis pseudoglioma syndrome (OPPGS) is a rare autosomal recessive disorder characterised by congenital or juvenile-onset blindness, severe juvenile-onset osteoporosis, and skeletal fragility. OPPGS is caused by loss-of-function mutations in the LRP5 gene, a member of the LDL receptor family. It activates the canonical Wnt/β-catenin pathway, regulating osteoblastic bone formation. We investigated a 40-year-old Caucasian male presenting with congenital blind...