ORIGINAL ARTICLE An SNP site in pri-miR-124, a brain expressed miRNA gene, no contribution to mesial temporal lobe epilepsy in an Italian sample Ida Manna 1 • Angelo Labate 2 • Giuseppe Borzı ` 2 • Laura Mumoli 2 • Salvatore Maria Cavalli 2 • Miriam Sturniolo 2 • Aldo Quattrone 1,2 • Antonio Gambardella 1,2 Received: 18 February 2016 / Accepted: 29 April 2016 Ó Springer-Verlag Italia 2016 Abstract Mesial temporal lobe epilepsy (MTLE) is the most common type of refractory epilepsy and is usually associated with hippocampal sclerosis (Hs). The pathogen- esis of MTLE involves many biological pathways, some of which seem to be regulated by microRNAs (miRNAs). Increasing evidence shows that single nucleotide polymor- phisms (SNPs) or mutations in miRNAs sequence may affect the processing and function of miRNAs and partici- pate in the occurrence of diseases. In this study, the effect of the SNP of one neuronal miRNA, miR-124, on susceptibility to MTLE was investigated using a case control study. To understand the role, a common C/G polymorphism desig- nated rs531564 in the molecular mechanisms of MTLE, we sought to determine whether this genetic variant could influence susceptibility to disease in a cohort of 307 MTLE patients and 306 healthy controls, using TaqMan allelic discrimination assay, on an Applied Biosystems PCR plat- form. No statistically significant differences were found in the allele or genotype distributions of the miR-124 rs531564 polymorphism among MTLE patients and MTLE-free con- trol subjects (p [ 0.05). Our results demonstrate that this SNP has no major role in genetic susceptibility to MTLE, at least in the population studied here. Keywords miR-124a Á Mesial temporal lobe epilepsy Á Genetic susceptibility Á Single nucleotide polymorphism Á Association studies Introduction Mesial temporal lobe epilepsy (MTLE) is the most com- mon form of epilepsy and is also responsible for a majority of refractory epilepsy [1]. Many patients with MTLE develop pharmacoresistance, and the most common pathological finding in patients with refractory MTLE is hippocampal sclerosis (Hs). The biologic processes that are most frequently identified as components of Hs pathogen- esis through several functional studies are glial activation, immune response, synaptic transmission, signal transduc- tion, ion transport, and synaptic plasticity. Although the mechanisms underlying epileptogenesis remain uncertain, synaptic reorganization of hippocampal structures is a potential mechanism explaining hippocampal hyperex- citability in patients with intractable MTLE. Genetic fac- tors, together with environmental conditions, contribute to the etiology of sporadic MTLE [2]. Exploration of classical candidate genes, involved in MTLE, has identified a few consistent risk factors for susceptibility to disease, sug- gesting that additional loci await discovery. The search for genetic factors predisposing to the disease has recently indicated that also genetic variations in regulatory regions could give a contribution to the phenotype. More recently, dysregulation of small noncoding RNAs, particularly microRNAs (miRNAs), has achieved significant attention in relation to epilepsy [3, 4]. miRNAs represent an evo- lutionarily conserved class of endogenous, *22 nucleo- tide, non-coding RNAs that act as small regulatory molecules that post-transcriptional regulate target gene & Antonio Gambardella a.gambardella@unicz.it 1 Institute of Molecular Bioimaging and Physiology (IBFM), National Research Council, Section of Germaneto, Catanzaro 88100, Italy 2 Department of Medical Sciences, Institute of Neurology, University Magna Graecia, Catanzaro 88100, Italy 123 Neurol Sci DOI 10.1007/s10072-016-2597-7