Sex bias in autism spectrum disorder in neurofibromatosis type 1

• Published in: Journal of neurodevelopmental disorders Vol. 8; no. 1; p. 26
• Main Authors: Garg, Shruti, Heuvelman, Hein, Huson, Susan, Tobin, Hannah, Green, Jonathan
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 26.07.2016; BioMed Central
• Subjects: Analysis; Animal cognition; Attention deficit hyperactivity disorder; Autism; Behavior; Bias; Biomedical research; Cognitive ability; Communication; Females; Field study; Gender differences; Genes; Genotype & phenotype; Hyperactivity; Language disorders; Males; Neurofibromatosis; Neurosciences; Pervasive developmental disorders; Risk factors; Sex differences (Biology); Social aspects; United Kingdom; Neurofibromatosis type 1; Syndromic autism; Autism spectrum disorder; Sex bias
• ISSN: 1866-1947; 1866-1955
• DOI: 10.1186/s11689-016-9159-4

Despite extensive literature, little is known about the mechanisms underlying sex bias in autism spectrum disorder (ASD). This study investigates the sex differences in ASD associated with neurofibromatosis type 1, a single-gene model of syndromic autism. We analysed data from n = 194 children aged 4-16 years with neurofibromatosis type 1. Sex differences were evaluated across the Autism Diagnostic Interview-Revised (ADI-R), Autism Diagnostic Observation Schedule (ADOS), verbal IQ, Social Responsiveness Scale (SRS) and Conners questionnaires. There was 2.68:1 male:female ratio in children meeting ASD criteria on the deep phenotyping measures. On symptom profile, males with neurofibromatosis type 1 (NF1) + ASD were more impaired on reciprocal social interaction and communication domains of the ADI-R but we found no differences on the restricted, repetitive behaviours (RRBs) domain of the ADI-R and no differences on the social on the ADOS. NF1 ASD males and females were comparable on verbal IQ, and the inattention/hyperactivity domains of the Conners questionnaire. There is a significant male bias in the prevalence of ASD in NF1. The phenotypic profile of NF1 + ASD cases includes greater social communication impairment in males. We discuss the implications of our findings and the rationale for using NF1 as a model for investigating sex bias in idiopathic ASD.