RELN gene polymorphisms and susceptibility to epilepsy and schizophrenia: Clinical and genetic study of an Algerian family

Introduction - Several studies have shown a strong relationship between schizophrenia and epilepsy. This association implies a common genetic susceptibility for both conditions. This study aims to identify genetic variants of susceptibility to epilepsy and schizophrenia in an Algerian family.Patients and methods - All available members of this family underwent clinical and electroencephalographic evaluation. Genetic analysis by whole exome sequencing was performed after DNA extraction.Results - In this study, we report a family with two brothers having temporal lobe epilepsy associated to schizophrenia in one, and to recurrent depressive disorder in the other. Exome sequencing identified homozygous single nucleotide variant in theRELN gene (rs55689103) in patient with schizophrenia. His brother was heterozygous for the same variant.Conclusion - The polymorphism rs55689103 could be involved in schizophrenic phenotype in this family, but not in epilepsy phenotype. Further investigations of blood Reelin level and RELN promoter methylation are key components to interpreting the results of this study.