Could distal variants in ALG13 lead to atypical clinical presentation?

Congenital disorders of glycosylation (CDG) represent a wide range of some 150 inherited metabolic diseases, continually expanding in terms of newly identified genes and the heterogeneity of clinical and molecular presentations within each subtype. Heterozygous pathogenic variants in ALG13 are associated with early-onset epileptic encephalopathy, typically in females. The majority of subjects described so far harbour one of the two recurrent pathogenic variants, namely p.(Asn107Ser) and p.(Ala81Thr) in the C-terminal glycosyltransferase domain. We report a novel ALG13 variant (c.1709G > A, p.(Gly570Glu)) in an adult female with unremarkable past developmental and medical history, except for mild kinetic tremor.