Genetic analysis of 5'-untranslated region of voltage-gated sodium channel alpha 1-subunit gene in Dravet syndrome / 中华神经科杂志

ABSTRACT

Objective To screen and analyze nucleotide variants in 5'-untranslated region(5'-UTR)in voltage-gated sodium channel α1-subunit gene(SCN1A)in patients with Dravet syndrome and to evaluate the association of the variants with disease.Methods Peripheral blood of 24 patients with Dravet syndrome and 100 unrelated normal persons were collected and genomic DNA was extracted.PCR-sequencing of SCN1 A 5'-UTR in these DNA was performed.To evaluate the possibility of mutation inducing disease,bioinformatics analysis was applied to analyze the conservation of the sequences around the mutation site and predict the potential transcription elements.Results The nucleotide variant of 166.642.520G→A in exon 2 was identified in two patients,but not in normal controls.The mutation was a de novo mutation in a patient with early-onset.In the second proband,the mutation was also carried by his clinically asymptomatic mother.The nucleotide site 166.642.520 was moderately conserved in mammals(62.5%).The average nucleotide identity rate between human and other mammals species in the region adjacent to 166.642.520 was 88.5%.Two potential transcription regulatory elements were predicted on the sequence with the mutation of 166.642.520G>A,and only one on the sequence with wild-type.Conclusions The mutation 166.642.520G>A may be associated with Dravet syndrome and further studied should be performed to verify it and demonstrate its pathogenic mechanisms.