RFT1-CDG

RFT1-CDG (also known as RFT1-congenital disorder of glycosylation, formerly CDG-In) is an extremely rare autosomal recessive disorder caused by mutations in the RFT1 gene, which encodes a protein involved in the flipping of lipid-linked oligosaccharide intermediates across the endoplasmic reticulum membrane during N-linked glycosylation. This defect disrupts the proper glycosylation of proteins, leading to multisystem dysfunction. RFT1-CDG belongs to the broader group of congenital disorders of glycosylation (CDG), type I. Clinical features typically present in infancy and include severe intellectual disability, seizures (often intractable epilepsy), hypotonia, feeding difficulties, failure to thrive, and sensorineural hearing loss. Visual impairment, microcephaly, and hepatic involvement including coagulopathy and elevated liver transaminases may also be observed. Some patients exhibit inverted nipples and abnormal fat distribution, features sometimes seen in other CDG subtypes. Brain MRI may show cerebellar hypoplasia or other structural abnormalities. Diagnosis is supported by isoelectric focusing of serum transferrin showing a type 1 pattern (indicating a defect in the assembly or transfer of the lipid-linked oligosaccharide) and confirmed by molecular genetic testing of the RFT1 gene. There is currently no specific or curative treatment for RFT1-CDG. Management is supportive and symptomatic, including antiepileptic medications for seizure control, nutritional support, physical and occupational therapy, and management of hepatic and coagulation abnormalities. Only a small number of patients have been reported in the medical literature worldwide.

Common questions about RFT1-CDG