The RFT1 gene encodes an enzyme involved in N-linked glycosylation. This is a highly conserved process which involves the synthesis and processing of (N)-linked glycans or oligosaccharides on glycoproteins. It begins with the synthesis of a Man(5)GlcNAc(2)-dolichylpyrophosphate intermediate on the cytoplasmic side of the endoplasmic reticulum (ER) membrane. This intermediate is then translocated to the luminal side of the ER membrane. The RFT1 enzyme is responsible for catalyzing this translocation of Man(5)GlcNAc(2)-dolichylpyrophosphate.
Mutations in the RFT1 gene hence lead to enzymatic defects in N-linked glycosylation and are associated with Congenital Disorder of Glycosylation, Type In (CDG1N). This metabolic disorder results in severe developmental delay, mental retardation, seizures, myoclonus, hypotonia, microcephaly and failure to thrive.