Osteomesopyknosis: A Bone-Sclerosing Disorder that May be Confused with Bone Metastases.

Sclerosing bone disorders encompass a range of genetic and acquired diseases. The potential for bone metastases is often a significant concern, especially when multiple discrete lesions are present. Several non-malignant disorders can also produce similar patterns of bone abnormalities.

Osteomesopyknosis associated with a novel ALOX5 variant that impacts the RANKL pathway.

Background: Bone tissue homeostasis relies on the coordinated activity of the bone-forming osteoblasts and bone-resorbing osteoclasts. Osteomesopyknosis is considered a distinctive rare sclerosing skeletal disorder of unelucidated pathophysiology and presumably autosomal dominant transmission. However, the causal genes are unknown.

An LRP6 mutation (Arg360His) associated with low bone mineral density but not cardiovascular events in a Caucasian family.

Unlabelled: We present a family with a rare mutation of the LRP6 gene and for the first time provide evidence for its association with low bone mineral density.

Introduction: The Wnt pathway plays a critical role in bone homeostasis. Pathogenic variants of the Wnt co-receptor LRP6 have been associated with abnormal skeletal phenotypes or increased risk of cardiovascular events.

Genes and Variants Underlying Human Congenital Lactic Acidosis-From Genetics to Personalized Treatment.

Congenital lactic acidosis (CLA) is a rare condition in most instances due to a range of inborn errors of metabolism that result in defective mitochondrial function. Even though the implementation of next generation sequencing has been rapid, the diagnosis rate for this highly heterogeneous allelic condition remains low. The present work reports our group's experience of using a clinical/biochemical analysis system in conjunction with genetic findings that facilitates the taking of timely clinical decisions with minimum need for invasive procedures.

A new metabolic disorder in human cationic amino acid transporter-2 that mimics arginase 1 deficiency in newborn screening.

Purpose: We report a patient with a human cationic amino acid transporter 2 (CAT-2) defect discovered due to a suspected arginase 1 deficiency observed in newborn screening (NBS).

Methods: A NBS sample was analyzed using tandem mass spectrometry. Screen results were confirmed by plasma and urine amino acid quantification.

DPAGT1-CDG: Functional analysis of disease-causing pathogenic mutations and role of endoplasmic reticulum stress.

Pathogenic mutations in DPAGT1 are manifested as two possible phenotypes: congenital disorder of glycosylation DPAGT1-CDG (also known as CDG-Ij), and limb-girdle congenital myasthenic syndrome (CMS) with tubular aggregates. UDP-N-acetylglucosamine-dolichyl-phosphate N-acetylglucosamine phosphotransferase (GPT), the protein encoded by DPAGT1, is an endoplasmic reticulum (ER)-resident protein involved in an initial step in the N-glycosylation pathway. The aim of the present study was to examine the effect of six variants in DPAGT1 detected in patients with DPAGT1-CDG, and the role of endoplasmic reticulum stress, as part of the search for therapeutic strategies to use against DPAGT1-CDG.

Expression analysis revealing destabilizing mutations in phosphomannomutase 2 deficiency (PMM2-CDG): expression analysis of PMM2-CDG mutations.

Deficiency of phosphomannomutase (PMM2, MIM#601785) is the most common congenital disorder of glycosylation. Herein we report the genetic analysis of 22 Spanish PMM2 deficient patients and the functional analysis of 14 nucleotide changes in a prokaryotic expression system in order to elucidate their molecular pathogenesis. PMM2 activity assay revealed the presence of six protein changes with no enzymatic activities (p.

Functional analysis of three splicing mutations identified in the PMM2 gene: toward a new therapy for congenital disorder of glycosylation type Ia.

The congenital disorders of glycosylation (CDG) are a group of diseases caused by genetic defects affecting N-glycosylation. The most prevalent form of CDG-type Ia-is caused by defects in the PMM2 gene. This work reports the study of two new nucleotide changes (c.

Congenital disorder of glycosylation Ia: new differentially expressed proteins identified by 2-DE.

Congenital disorders of glycosylation (CDG) comprise a family of inherited multisystemic disorders resulting from the deficiency of glycosylation pathways. N-glycosylation defects are classified as two biochemical and genetic established types, of which CDG-Ia is the most frequent. We performed 2-DE proteomic analysis on serum from two functional hemizygous CDG-Ia patients bearing T237M and D65Y missense changes.