title: The Broad Autism (Endo)Phenotype: Neurostructural and Neurofunctional Correlates in Parents of Individuals with Autism Spectrum Disorders.
abstract: Autism Spectrum Disorders (ASD) are a set of neurodevelopmental disorders with an early-onset and a strong genetic component in their pathogenesis. According to genetic and epidemiological data, ASD relatives present personality traits similar to, but not as severe as the defining features of ASD, which have been indicated as the "Broader Autism Phenotype" (BAP). BAP features seem to be more prevalent in first-degree relatives of individuals with ASD than in the general population. Characterizing brain profiles of relatives of autistic probands may help to understand ASD endophenotype. The aim of this review was to provide an up-to-date overview of research findings on the neurostructural and neurofunctional substrates in parents of individuals with ASD (pASD). The primary hypothesis was that, like for the behavioral profile, the pASD express an intermediate neurobiological pattern between ASD individuals and healthy controls. The 13 reviewed studies evaluated structural magnetic resonance imaging (MRI) brain volumes, chemical signals using magnetic resonance spectroscopy (MRS), task-related functional activation by functional magnetic resonance imaging (fMRI), electroencephalography (EEG), or magnetoencephalography (MEG) in pASD.The studies showed that pASD are generally different from healthy controls at a structural and functional level despite often not behaviorally impaired. More atypicalities in neural patterns of pASD seem to be associated with higher scores at BAP assessment. Some of the observed atypicalities are the same of the ASD probands. In addition, the pattern of neural correlates in pASD resembles that of adult individuals with ASD, or it is specific, possibly due to a compensatory mechanism. Future studies should ideally include a group of pASD and HC with their ASD and non-ASD probands respectively. They should subgrouping the pASD according to the BAP scores, considering gender as a possible confounding factor, and correlating these scores to underlying brain structure and function. These types of studies may help to understand the genetic mechanisms involved in the various clinical dimension of ASD.
authors: Department of Clinical and Experimental Medicine, University of Pisa Pisa, Italy.
authors: Lucia
authors: L
authors: Billeci
authors: IRCCS Stella Maris Foundation Pisa, Italy.
authors: Sara
authors: S
authors: Calderoni
authors: Department of Clinical and Experimental Medicine, University of PisaPisa, Italy; Department of Sciences for Health Promotion and Mother and Child Care G. D'Alessandro, University of PalermoPalermo, Italy.
authors: Eugenia
authors: E
authors: Conti
authors: Department of Clinical and Experimental Medicine, University of Pisa Pisa, Italy.
authors: Camilla
authors: C
authors: Gesi
authors: Department of Clinical and Experimental Medicine, University of Pisa Pisa, Italy.
authors: Claudia
authors: C
authors: Carmassi
authors: Department of Clinical and Experimental Medicine, University of Pisa Pisa, Italy.
authors: Liliana
authors: L
authors: Dell'Osso
authors: Department of Clinical and Experimental Medicine, University of PisaPisa, Italy; IRCCS Stella Maris FoundationPisa, Italy.
authors: Giovanni
authors: G
authors: Cioni
authors: Department of Clinical and Experimental Medicine, University of PisaPisa, Italy; IRCCS Stella Maris FoundationPisa, Italy.
authors: Filippo
authors: F
authors: Muratori
authors: Department of Clinical and Experimental Medicine, University of PisaPisa, Italy; IRCCS Stella Maris FoundationPisa, Italy.
authors: Andrea
authors: A
authors: Guzzetta
keywords: Autism Spectrum Disorders; Broader Autism Phenotype; electroencephalography; magnetic resonance imaging; magnetic resonance spectroscopy; magnetoenchephalography; parents