Posts By: pcampeau

Pathophysiology of UCDs

Posted by & filed under Part 08: AMINO ACIDS.

Ammonia accumulation in urea cycle defects (UCDs) leads to several cellular dysfunctions such as amino acid disturbances and disrupted neurotransmitter signaling (reviewed in Braissant et al, 2010, Mol Genet Metab 100 Suppl 1:S3-S12). Also, the pathophysiology of UCDs does not simply involve ammonia, and this is clinically supported by the fact that specific clinical features […]

New CDG: SRD5A3

Posted by & filed under New IEM.

There are over 40 known congenital disorders of glycosylation (CDGs), and a reformulation of their nomenclature has been proposed by Dr. Jaak Jaeken, who described the first CDG (Jaeken et al, 2009, Biochim Biophys Acta 1792:825-6). A new CDG has now been identified in several families (Cantagrel et al, 2010, Cell 142:203-17). Patients present notably […]

Genetic Alliance 25th

Posted by & filed under In the news.

Genetic Alliance is a nonprofit health advocacy organization that improves health through the authentic engagement of communities and individuals. This year, they are celebrating their 25th anniversary as a journey toward novel partnerships, connected consumers, and smart services. They are hosting a variety of events throughout the year, including monthly salons around the country and […]

Inborn error of endocannabinoid metabolism

Posted by & filed under New IEM.

An inborn error of endocannabinoid metabolism has been described in 19 patients (Fiskerstrand et al. 2010, Am J Hum Genet 87:410-7), clinically characterized by polyneuropathy, hearing loss, ataxia, retinitis pigmentosa, and cataracts (PHARC). ABHD12 as an integral membrane protein with an active site located on the extracellular side. The mutated enzyme normally hydrolyzes 2-arachidonoyl glycerol, […]

CDG-IIL

Posted by & filed under New IEM.

The conserved oligomeric Golgi (COG) complex is located in the cytosol and aids in the sorting and glycosylation of Golgi-resident enzymes and secreted proteins. A new congenital disorder of glycosylation has been described involving this complex: CDG-IIL caused by COG6 mutations (Lübbehusen et al., 2010, Hum Mol Genet 19:3623-33). Clinical presentation is a severe neurologic […]

Isocitrate dehydrogenase

Posted by & filed under New IEM.

IDH2, encoding mitochondrial isocitrate dehydrogenase 2 has been shown last year to be mutated in various tumors, providing a new link between intermediary metabolism and cancer. This prompted Martijn Kranendijk et al. to study this gene in patients with D-2-Hydroxyglutaric Aciduria. While some are asymptomatic, others have developmental delay, epilepsy, hypotonia, cardiomyopathy and dysmorphic features.  […]

New IEMs

Posted by & filed under New IEM.

Two new mitochondrial diseases have been described: an encephalomyopathy caused by mutations in C12orf65 leading to a mitochondrial translation defect (Antonicka et al., 2010, Am J Hum Genet 87:115-22). The mutated protein is thought to help tRNA processing during mitochondrial protein elongation. Also, mutations in the X-linked AIFM1 gene, encoding the protein Apoptosis-Inducing Factor Mitochondrion-associated […]

Primary hyperoxaluria type III

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Primary hyperoxaluria type III is caused by mutations in DHDPSL, which encodes a protein which could synthesize glyoxalate, and activating mutations would increase glyoxalate and then oxalate accumulation Belostotsky R, Seboun E, Idelson GH, Milliner DS, Becker-Cohen R, Rinat C, et al. Mutations in DHDPSL are responsible for primary hyperoxaluria type III. American journal of […]

Renal Fanconi with mutations in NaPi-IIa

Posted by & filed under New IEM.

A renal Fanconi syndrome has been described with mutations in NaPi-IIa causing impared renal phosphate reabsorption Magen D, Berger L, Coady MJ, Ilivitzki A, Militianu D, Tieder M, et al. A loss-of-function mutation in NaPi-IIa and renal Fanconi’s syndrome. [Internet]. The New England journal of medicine. 2010 ;362(12):1102-9.Available from: http://www.ncbi.nlm.nih.gov/pubmed/20335586 Philippe Campeau Baylor College of […]

ERT for late-onset Pompe disease

Posted by & filed under Part 16: LYSOSOMAL DISORDERS, Part 25: MUSCLE.

van der Ploeg AT et al. A randomized study of alglucosidase alfa in late-onset Pompe’s disease. N Engl J Med. 2010 Apr 15;362(15):1396-406 In this study, alglucosidase alfa resulted in improved walking distance and stabilization of pulmonary function for patients with late-onset Pompe’s disease. posted by Philippe Campeau