Autism spectrum disorder (ASD) is a devastating and common neurodevelopmental disorder and a major public health concern. Fragile X syndrome is the leading known genetic cause of autism, and both fragile X syndrome and the FMR1 premutation are highly associated with autism with ~70% and ~20% meeting DSM- criteria respectively. This proposal extends our initial study, Emergence and Stability of Autism in Fragile X, focused on behavioral symptoms and biomarkers of ASD risk in infants with fragile X syndrome and fragile X premutation at 6,9,12 and 24 months contrasted to siblings of children with idiopathic ASD and typical controls. This proposal represents longitudinal surveillance at 3, 4 and 5 years-of-age in our cohort of 158 infant participants. Our initial findings have fueled a new set of questions to enhance our knowledge of the emergence of ASD features, diagnoses and associated features in FXS and FXpm, including the prevalence and stability of ASD diagnoses FXpm, the stability of ASD core features focused across a continuum, the association of atypical attention and social fear as additive or independent associated features and the predictive value of infant-derived prodromal features to ASD diagnoses across preschool.

Public Health Relevance

Autism is a Devastating and Common Developmental Disorder that is a Major Public Health Concern. Fragile X syndrome is the leading known genetic cause of autism, and both FXS and the FMR1 premutation are highly associated with autism. There is considerable interest in studying the association of FX-disorders contrasted to idiopathic autism spectrum disorder due to the clinical consequences of their co-occurrence in FX and implications for increased understanding of ASD.

National Institute of Health (NIH)
National Institute of Mental Health (NIMH)
Research Project (R01)
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Child Psychopathology and Developmental Disabilities Study Section (CPDD)
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Gilotty, Lisa
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University of South Carolina at Columbia
Schools of Arts and Sciences
United States
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Adlof, Suzanne M; Klusek, Jessica; Hoffmann, Anne et al. (2018) Reading in Children With Fragile X Syndrome: Phonological Awareness and Feasibility of Intervention. Am J Intellect Dev Disabil 123:193-211
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