title: HERVs expression in Autism Spectrum Disorders.
abstract: BACKGROUND
  Autistic Spectrum Disorder (ASD) is a heterogeneous neurodevelopmental disorder, resulting from complex interactions among genetic, genomic and environmental factors. Here we have studied the expression of Human Endogenous Retroviruses (HERVs), non-coding DNA elements with potential regulatory functions, and have tested their possible implication in autism.
  
  
  METHODS
  The presence of retroviral mRNAs from four HERV families (E, H, K and W), widely implicated in complex diseases, was evaluated in peripheral blood mononuclear cells (PBMCs) from ASD patients and healthy controls (HCs) by qualitative RT-PCR. We also analyzed the expression of the env sequence from HERV-H, HERV-W and HERV-K families in PBMCs at the time of sampling and after stimulation in culture, in both ASD and HC groups, by quantitative Real-time PCR. Differences between groups were evaluated using statistical methods.
  
  
  RESULTS
  The percentage of HERV-H and HERV-W positive samples was higher among ASD patients compared to HCs, while HERV-K was similarly represented and HERV-E virtually absent in both groups. The quantitative evaluation shows that HERV-H and HERV-W are differentially expressed in the two groups, with HERV-H being more abundantly expressed and, conversely, HERV-W, having lower abundance, in PBMCs from ASDs compared to healthy controls. PMBCs from ASDs also showed an increased potential to up-regulate HERV-H expression upon stimulation in culture, unlike HCs. Furthermore we report a negative correlation between expression levels of HERV-H and age among ASD patients and a statistically significant higher expression in ASD patients with Severe score in Communication and Motor Psychoeducational Profile-3.
  
  
  CONCLUSIONS
  Specific HERV families have a distinctive expression profile in ASD patients compared to HCs. We propose that HERV-H expression be explored in larger samples of individuals with autism spectrum in order to determine its utility as a novel biological trait of this complex disorder.
authors.affiliation: Department of Experimental Medicine and Biochemical Sciences, University of Rome "Tor Vergata", Rome, Italy.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Balestrieri
authors.forename: Carla
authors.initials: C
authors.lastname: Arpino
authors.forename: Claudia
authors.initials: C
authors.lastname: Matteucci
authors.forename: Roberta
authors.initials: R
authors.lastname: Sorrentino
authors.forename: Francesca
authors.initials: F
authors.lastname: Pica
authors.forename: Riccardo
authors.initials: R
authors.lastname: Alessandrelli
authors.forename: Antonella
authors.initials: A
authors.lastname: Coniglio
authors.forename: Paolo
authors.initials: P
authors.lastname: Curatolo
authors.forename: Giovanni
authors.initials: G
authors.lastname: Rezza
authors.forename: Fabio
authors.initials: F
authors.lastname: Macciardi
authors.forename: Enrico
authors.initials: E
authors.lastname: Garaci
authors.forename: Simona
authors.initials: S
authors.lastname: Gaudi
authors.forename: Paola
authors.initials: P
authors.lastname: Sinibaldi-Vallebona
mesh_terms: D002648:Child; D002659:Child Development Disorders, Pervasive / Q000821:virology*; D002675:Child, Preschool; D020077:Endogenous Retroviruses / Q000235:genetics* / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D012367:RNA, Viral