Total submissions: 1
| Submitter | RCV | SCV | Clinical significance | Condition | Last evaluated | Review status | Method | Comment |
|---|---|---|---|---|---|---|---|---|
| Invitae | RCV000803742 | SCV000943627 | likely pathogenic | Early infantile epileptic encephalopathy with suppression bursts | 2023-11-02 | criteria provided, single submitter | clinical testing | This sequence change replaces glycine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 343 of the SCN1A protein (p.Gly343Ala). This variant also falls at the last nucleotide of exon 7, which is part of the consensus splice site for this exon. This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with clinical features of developmental and epileptic encephalopathy (PMID: 31440721; Invitae). ClinVar contains an entry for this variant (Variation ID: 648913). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). This variant disrupts the p.Gly343 amino acid residue in SCN1A. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 28012175). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. |