DOLK encodes dolichol kinase, an endoplasmic reticulum membrane protein that catalyzes the final, CTP-dependent phosphorylation step in dolichyl monophosphate (Dol-P) biosynthesis 1. Dol-P functions as an essential oligosaccharide carrier required for N-linked and O-linked glycosylation and GPI anchor synthesis 1. The ER N-glycosylation pathway involving DOLK is evolutionarily conserved across multiple organisms 1. DOLK deficiency causes congenital disorder of glycosylation type 1M (DOLK-CDG), a severe autosomal recessive condition with early infantile onset and poor prognosis 2. DOLK-CDG manifests as a multi-system disorder affecting cardiac, cutaneous, neurological, and skeletal tissues 2. Clinical presentations include congenital heart disease, ichthyosis-like skin manifestations, developmental delay, hypotonia, and seizures, with affected individuals typically experiencing early mortality from multiple organ failure 2. DOLK is one of 29 genes associated with congenital disorders of glycosylation presenting cardiac complications, highlighting the critical importance of glycosylation in cardiac development and function 3. Novel compound heterozygous mutations (c.1268C>G and c.1581_1583del) have been identified, expanding the known DOLK mutation spectrum 2.