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 (LÃ¼bbehusen et al., 2010, Hum Mol Genet 19:3623-33). Clinical presentation is a severe neurologic disease with vitamin K deficiency, intracranial bleedings, seizures, and death in infancy. COG6 encodes the subunit 6 of the COG complex and cells from the identified patient displayed slower retrograde transport of proteins from the Golgi.
Philippe Campeau, MD