SIGNIFICANCE OF TARGETED EXOME SEQUENCING AND METHODS OF DATA ANALYSIS IN THE DIAGNOSIS OF GENETIC DISORDERS LEADING TO THE DEVELOPMENT OF EPILEPTIC ENCEPHALOPATHY

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Tatyana Victorovna Kozhanova

Abstract

Epilepsy is the most common serious neurological disorder, and there is a genetic basis in almost 50% of people with epilepsy. The diagnosis of genetic epilepsies makes to estimate reasons of seizures in the patient. Last decade has shown tremendous growth in gene sequencing technologies, which have made genetic tests available. The aim is to show significance of targeted exome sequencing and methods of data analysis in the diagnosis of hereditary syndromes leading to the development of epileptic encephalopathy. We examined 27 patients with с early EE (resistant to antiepileptic drugs), psychomotor and speech development delay in the psycho-neurological department. Targeted exome sequencing was performed for patients without a previously identified molecular diagnosis using 454 Sequencing GS Junior sequencer (Roche) and IlluminaNextSeq 500 platform. As a result of the analysis, specific epilepsy genetic variants were diagnosed in 27 patients. The greatest number of cases was due to mutations in the SCN1A gene (7/27). The structure of mutations for other genes (mutations with a minor allele frequency of less than 0,5% are presented): ALDH7A1 (n=1), CACNA1C (n=1), CDKL5 (n=1), CNTNAP2 (n=2), DLGAP2 (n=2), DOCK7 (n=2), GRIN2B (n=2), HCN1 (n=1), NRXN1 (n=3), PCDH19 (n=1), RNASEH2B (n=2), SLC2A1 (n=1), UBE3A (n=1). The use of the exome sequencing in the genetic practice allows to significantly improve the effectiveness of medical genetic counseling, as it made possible to diagnose certain variants of genetically heterogeneous groups of diseases with similar of clinical manifestations.

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How to Cite
KOZHANOVA, Tatyana Victorovna. SIGNIFICANCE OF TARGETED EXOME SEQUENCING AND METHODS OF DATA ANALYSIS IN THE DIAGNOSIS OF GENETIC DISORDERS LEADING TO THE DEVELOPMENT OF EPILEPTIC ENCEPHALOPATHY. Journal of Bioinformatics and Genomics, [S.l.], n. 2 (4), aug. 2017. ISSN 2530-1381. Available at: <http://journal-biogen.org/article/view/59>. Date accessed: 20 aug. 2017. doi: http://dx.doi.org/10.18454/jbg.2017.2.4.2.
Section
Genome analysis
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