Epileptic encephalopathy

Gene: SLC35A2

Comment on list classification: Updated rating from Red to Green: SLC35A2 added to panel after March 2017 OMIM updates. 2 papers with 4 unrelated patients supporting association between SLC35A2 and EE. Green rating confirmed by Arianna Tucci.

Created: 11 May 2017, 12:08 p.m.

In 3 unrelated Japanese girls with early infantile epileptic encephalopathy (age 8, 10 and 12), Kodera et al. (2013, PMID:24115232) identified 3 different de novo heterozygous mutations in the SLC35A2 gene. 2 of the mutations resulted in truncated proteins, suggesting a loss of function, and 1 was a missense mutation with no functional studies.

Created: 11 May 2017, 12:07 p.m.

PMID:27743886 (Kimizu et al., 2017) report a female infant with early onset epileptic encephalopathy and developmental delay (amongst other symptoms). She had a frameshift mutation (c.950delG, p.Gly317Alafs*32) in SLC35A2.

Created: 11 May 2017, 12:07 p.m.

Mode of inheritance
X-LINKED: hemizygous mutation in males, monoallelic mutations in females may cause disease (may be less severe, later onset than males)

Phenotypes
Congenital disorder of glycosylation, type IIm, 300896 (includes Epileptic encephalopathy); Epileptic encephalopathy, early infantile, 22 (EIEE22); early-onset epileptic encephalopathy

Publications

• 24115232