COG7 is a subunit of the conserved oligomeric Golgi (COG) complex, a multisubunit tethering complex essential for Golgi structure and function 1. As part of the COG complex's lobe B, COG7 mediates vesicle docking and fusion at the Golgi apparatus and cooperates with Rab1 and other trafficking regulators to maintain proper Golgi organization and retrograde transport 23. COG7 enables recruitment of regulatory proteins like Rab11 and phosphatidylinositol transfer proteins to membrane addition sites during cytokinesis 1. The protein is critical for glycoprotein biosynthesis, particularly N-glycosylation and O-glycosylation pathways 4. COG7 mutations cause Congenital Disorder of Glycosylation type IIe (CDG-IIe), characterized by progressive microcephaly, growth retardation, hypotonia, cardiac defects, and characteristic cutis laxa with wrinkled skin 56. Patient mutations lead to severe reduction in COG subunits and combined N- and O-linked glycosylation defects with hyposialylation 5. In model organisms, COG7 loss impairs Golgi architecture, neuromotor development, and synaptic function 2. Recent genome-wide association studies identify COG7 variants associated with Alzheimer's disease susceptibility 7. These findings establish COG7 as a critical determinant of Golgi functional integrity required for cellular metabolism and neurological homeostasis.