Rare Epilepsy Syndromes and the Congenital Disorders of Glycosylation

Rare Epilepsy Syndromes. Motivated by a recent paper in JIMD Reports, I wanted to use this post to present a very rare group of disorders, in which glycosylation of a variety of tissue proteins and/or lipids is deficient. These so-called congenital disorders of glycosylation (CDG) are a highly heterogeneous group of recessive disorders that you might be confronted with. As CDG may masquerade as otherwise non-specific epileptic encephalopathies, you might encounter them clinically or by browsing through exomes of patients with RES. Imtiaz and colleagues now report on two brothers in a large Saudi family with 18 affected siblings. They identified a mutation in DPAGT1, which is known to cause CDG Ij.   Continue reading

A new twist on an old gene: EFHC1 in epileptic encephalopathy

A peculiar gene. There is one gene in the small world of epilepsy genetics that has always troubled me. A gene that has an unknown function and is not expressed in the postnatal brain, but is well established as one of the few genes for autosomal dominant Juvenile Myoclonic Epilepsy (JME). This gene is EFHC1. Now, a recent paper in Epilepsia reports EFHC1 as a possible candidate gene in autosomal recessive epileptic encephalopathy with neonatal onset. The mystery surrounding this gene continues. Continue reading