Purpose: The "Fragile X Messenger Ribonucleoprotein-1 (FMR1)" premutation (FXpm) is a genetic variant that is common in the general population and is associated with health symptoms and disease in adulthood. However, poor understanding of the clinical phenotype during childhood has hindered the development of clinical practice guidelines…

There is a critical need for validated screening tools for autism spectrum disorder in very young children so families can access tailored intervention services as early as possible. Few screeners exist for children between the recommended screening ages of 18-24 months. This study examined the utility of a new autism-specific parent-report…

Purpose: No diagnostic tools exist for identifying social (pragmatic) communication disorder (SPCD), a new "Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition" category for individuals with social communication deficits but not the repetitive, restricted behaviors and interests (RRBIs) that would qualify them for a…

Autism spectrum disorder (ASD) is characterized by a variety of social and non-social behavioral deficits. One potential mechanism that could unify this diverse profile of behaviors is slower processing speed. Seventy-six high-functioning adults with ASD were compared to 64 matched controls on standardized measures of processing speed.…

This study was a replication of Mazefsky et al.'s ("Journal of Autism and Developmental Disabilities" 43:1236-1242, 2013) investigation among a sample of 45 high ability children and adolescents diagnosed with ASD under DSM-IV-TR. Items from the ADOS and ADI-R were mapped onto DSM-5 diagnostic criteria for ASD and SCD to determine…

The prevalence of autism spectrum disorder (ASD) in many genetic disorders is well documented but not as yet in Mucopolysaccharidosis type III (MPS III). MPS III is a recessively inherited metabolic disorder and evidence suggests that symptoms of ASD present in MPS III. This systematic review examined the extant literature on the symptoms of ASD…

A growing number of research groups are now including older minimally verbal individuals with autism spectrum disorder in their studies to encompass the full range of heterogeneity in the population. There are numerous barriers that prevent researchers from collecting high-quality data from these individuals, in part because of the challenging…

Tests of mediation in treatment trials can illuminate processes of change and suggest causal influences in development. We conducted a mediation analysis of a previously published randomised controlled trial of parent-mediated communication-focused treatment for autism against ordinary care, with 28 children aged 2-5 years (Aldred et al. in J…

Efforts to understand the causes of autism spectrum disorders (ASDs) have been hampered by genetic complexity and heterogeneity among individuals. One strategy for reducing complexity is to target endophenotypes, simpler biologically based measures that may involve fewer genes and constitute a more homogenous sample. A genome-wide association…

While there is a strong sex bias in the presentation of autism, it is unknown whether this bias is also present in subclinical manifestations of autism among relatives, or the broad autism phenotype. This study examined this question and investigated patterns of co-occurrence of broad autism phenotype traits within families of individuals with…

Little is known about whether early symptom presentation differs in toddlers with ASD from ethnic minority versus non-minority backgrounds. Within a treatment study for toddlers with ASD, we compared 19 minority to 65 Caucasian children and their parents on variables obtained from the Mullen Scales of Early Learning, Autism Diagnostic Observation…

Communication spontaneously initiated by infants at heightened risk (HR; n = 15) for autism spectrum disorders (ASD) is compared with that in low-risk (LR; n = 15) infants at 13 and 18 months of age. Infants were observed longitudinally during naturalistic in-home interaction and semistructured play with caregivers. At both ages, HR infants…

Background: Autism spectrum disorder (ASD) is characterized by notable phenotypic heterogeneity, which is often viewed as an obstacle to the study of its etiology, diagnosis, treatment, and prognosis. On the basis of empirical evidence, instead of three binary categories, the upcoming edition of the DSM 5 will use two dimensions--social…