A Genetic Multimutation Model of Autism Spectrum Disorder Fits Disparate Twin Concordance Data from the USA and Canada

Whether autism spectrum disorder (ASD) is caused by genetics, environmental factors, or a combination of both is still being debated today. To help resolve this issue, a genetic multimutation model of ASD development was applied to a wide variety of age-of-onset data from the USA and Canada, and the model is shown to fit all the data. Included in this analysis is new, updated data from the Interactive Autism Network (IAN) of the Kennedy Krieger Institute in Baltimore, Maryland. We find that the age-of-onset distribution for males and females is identical, suggesting that ASD may be an autosomal disorder. The ASD monozygote concordance rate in twin data predicted by the genetic multimutation model is shown to be compatible with the observed rates. If ASD is caused entirely by genetics, then the ASD concordance rate of a cohort of monozygote twins should approach 100% as the youngest pair of twins in the cohort passes 10 years of age, a prediction that constitutes a critical test of the genetic hypothesis. Thus, by measuring the ASD concordance rate as a cohort of monozygote twins age, the hypothesis that this disorder is caused entirely by genetic mutations can be tested.

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Effects of Diagnostic Severity upon Sex Differences in Behavioural Profiles of Young Males and Females with Autism Spectrum Disorder

Journal of Autism and Developmental Disorders ◽

10.1007/s10803-019-04159-x ◽

2019 ◽

Vol 49 (11) ◽

pp. 4429-4440 ◽

Cited By ~ 1

Author(s):

Vicki Bitsika ◽

Christopher F. Sharpley

Keyword(s):

Autism Spectrum Disorder ◽

Sex Differences ◽

Autism Spectrum ◽

Spectrum Disorder ◽

Young Males ◽

Males And Females ◽

Females With Autism

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Clinical and Genetic Profile of Autism Spectrum Disorder–Epilepsy (ASD-E) Phenotype: Two Sides of the Same Coin!

Clinical EEG and Neuroscience ◽

10.1177/1550059420909673 ◽

2020 ◽

Vol 51 (6) ◽

pp. 390-398 ◽

Cited By ~ 2

Author(s):

Sudhakar Karunakaran ◽

Ramshekhar N. Menon ◽

Sruthi S. Nair ◽

S. Santhakumar ◽

Muralidharan Nair ◽

...

Keyword(s):

Autism Spectrum Disorder ◽

Age Of Onset ◽

Focal Epilepsy ◽

Diagnostic Yield ◽

Autism Spectrum ◽

Spectrum Disorder ◽

Chromosomal Microarray ◽

Seizure Type ◽

Epilepsy Syndrome ◽

Genetic Profile

The clinical phenotype of autism spectrum disorder and epilepsy (ASD-E) is a common neurological presentation in various genetic disorders, irrespective of the underlying pathophysiological mechanisms. Here we describe the demographic and clinical profiles, coexistent neurological conditions, type of seizures, epilepsy syndrome, and EEG findings in 11 patients with ASD-E phenotype with proven genetic etiology. The commonest genetic abnormality noted was CDKL5 mutation (3), MECP2 mutation (2), and 1p36 deletion (2). The median age of onset of clinical seizures was 6 months (range, 10 days to 11 years). The most common seizure type was focal onset seizures with impaired awareness, observed in 7 (63.6%) patients followed by epileptic spasms in 4 (30.8%), generalized tonic-clonic and atonic seizures in 3 (27.3%) patients each and tonic seizures in 2 (18.2%) patients and myoclonic seizures in 1 (9.1%) patient. Focal and multifocal interictal epileptiform abnormalities were seen in 6 (54.6%) and 5 (45.5%) patients, respectively. Epileptic encephalopathy and focal epilepsy were seen in 7 (63.6%) and 4 (36.4%) patients, respectively. The diagnostic yield of genetic testing was 44% (11 of 25 patients) and when variants of unknown significance and metabolic defects were included, the yield increased to 60% (15 of 25 patients). We conclude that in patients with ASD-E phenotype with an underlying genetic basis, the clinical seizure type, epilepsy syndrome, and EEG patterns are variable. Next-generation exome sequencing and chromosomal microarray need to be considered in clinical practice as part of evaluation of children with ASD-E phenotype.

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Potential explanations of behavioural and other differences and similarities between males and females with autism spectrum disorder

Early Human Development ◽

10.1016/j.earlhumdev.2019.104863 ◽

2020 ◽

Vol 140 ◽

pp. 104863

Author(s):

William H. James ◽

Victor Grech

Keyword(s):

Autism Spectrum Disorder ◽

Autism Spectrum ◽

Spectrum Disorder ◽

Males And Females ◽

Females With Autism

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Preliminary investigation of interdisciplinary trainee’s improvement in knowledge about autism spectrum disorder

Advances in Autism ◽

10.1108/aia-06-2020-0035 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Tybytha D. Ryan ◽

Maryellen Brunson McClain ◽

Anna Merrill ◽

Naima Dahir ◽

Bryn Harris ◽

...

Keyword(s):

Autism Spectrum Disorder ◽

Preliminary Investigation ◽

Core Competency ◽

Practical Experience ◽

Autism Spectrum ◽

Leadership Education ◽

Spectrum Disorder ◽

Content Type ◽

Significant Difference ◽

The Usa

Purpose Individuals with autism spectrum disorder (ASD) often receive services from a variety of professionals. However, not all providers receive adequate training in ASD. The Leadership Education in Neurodevelopmental and Related Disabilities (LEND) program includes a core competency of increasing knowledge about neurodevelopmental and related disabilities. This study attempted to assess trainees’ ASD knowledge and self-reported confidence in working with individuals with ASD and sought to understand if training through the LEND program increases these competencies. Additionally, the purpose of this study is to determine factors that predict ASD knowledge and self-reported confidence in providing services to this population, specifically in an interdisciplinary trainee sample. Design/methodology/approach Participants were 170 interdisciplinary LEND trainees during the 2017–2018 academic year. Participants across the USA completed online pre- and posttraining surveys. The survey included demographics, ASD knowledge, questions assessing training experiences, perceived ASD knowledge and self-reported confidence. Findings A one-way analysis of variance determined that there was a statistically significant difference in measured ASD knowledge across disciplines F(7, 148) = 5.151, p < .001. Clinical trainees (e.g. psychology, pediatrics and speech) exhibited more measured ASD knowledge than nonclinical trainees (e.g. neuroscience, legal). Additionally, training experiences, self-reported confidence and perceived ASD knowledge were predictors of measured ASD knowledge. Moreover, trainees increased their measured ASD knowledge, self-reported confidence and had more experiences with individuals who have ASD at the end of the training year. Originality/value These findings suggest that the LEND program may assist in the preparation of professionals to work with individuals with ASD. Training opportunities, including educational and practical experience, to train interdisciplinary providers who will work with individuals with ASD are advised.

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Sex differences in employment and supports for adults with autism spectrum disorder

Autism ◽

10.1177/1362361319827417 ◽

2019 ◽

Vol 23 (7) ◽

pp. 1711-1719 ◽

Cited By ~ 2

Author(s):

Julie Lounds Taylor ◽

Leann Smith DaWalt ◽

Alison R Marvin ◽

J Kiely Law ◽

Paul Lipkin

Keyword(s):

Autism Spectrum Disorder ◽

Sex Differences ◽

Family Support ◽

The United States ◽

Autism Spectrum ◽

Spectrum Disorder ◽

Internet Survey ◽

Adults With Autism ◽

Males And Females ◽

Course Outcomes

This study explored sex differences in employment, reasons for unemployment, benefits, and supports among a large, international sample of adults with autism spectrum disorder. The sample included 443 adults with autism spectrum disorder (60% female; 74% residing in the United States) who consented to be part of an autism research registry and completed an Internet survey. Outcome variables included current employment status, number of hours working, number of jobs in the past 5 years, reasons for unemployment, as well as the number of benefits received and the amount of financial support currently being received from families of origin. Using multiple regression models, we found that males and females were working at similar rates. Females were more likely than males to say that their unemployment was a result of choosing to withdraw from the labor market. Similar percentages of males and females reported receiving some form of benefits or family support, but of those receiving benefits/family support, males received more than females. These results are consistent with other studies finding subtle, but potentially important sex differences in life-course outcomes of individuals with autism spectrum disorder.

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Exploring the Effect of Gender and Age on Stress and Emotional Distress in Adults With Autism Spectrum Disorder

Focus on Autism and Other Developmental Disabilities ◽

10.1177/1088357614549317 ◽

2014 ◽

Vol 33 (1) ◽

pp. 55-64 ◽

Cited By ~ 6

Author(s):

J. A. McGillivray ◽

H. T. Evert

Keyword(s):

Autism Spectrum Disorder ◽

Autism Spectrum ◽

Spectrum Disorder ◽

Personal Contact ◽

Adults With Autism ◽

Adult Females ◽

Depression Subscale ◽

Gender And Age ◽

Males And Females ◽

Gender And Age Differences

One hundred nine people with autism spectrum disorder (ASD) completed the Depression Anxiety Stress Scales (DASS), and Stress Survey Schedule (SSS). Compared with Australian norms for DASS depression, anxiety, and stress, both males and females with ASD showed elevated scores. Females aged 25 to 44 years scored significantly higher on the DASS depression subscale than same aged males and younger males and females. Significant gender and age differences were evident on SSS subscales. In comparison with males, females were more stressed on Pleasant Events, Sensory/Personal Contact, and Social and Environmental subscales, and adult females in particular were more stressed on items around Change and Social Threats and Anticipation/Uncertainty. Young people were less stressed on seven of the eight SSS subscales than older people. It appears that emotional vulnerability in people with ASD varies according to gender and age, with adult females at particular risk.

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Do sex differences affect ASD symptom severity scores?

10.13056/acamh.13247 ◽

2020 ◽

Keyword(s):

Autism Spectrum Disorder ◽

Sex Differences ◽

Symptom Severity ◽

Autism Spectrum ◽

Spectrum Disorder ◽

Severity Scores ◽

The Usa

Researchers in the USA have investigated whether standard diagnostic assessments for autism spectrum disorder (ASD) are biased against girls.

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Different aberrant mentalizing networks in males and females with autism spectrum disorders: Evidence from resting-state functional magnetic resonance imaging

Autism ◽

10.1177/1362361316667056 ◽

2016 ◽

Vol 22 (2) ◽

pp. 134-148 ◽

Cited By ~ 7

Author(s):

Jie Yang ◽

Jonathan Lee

Keyword(s):

Autism Spectrum Disorder ◽

Sex Differences ◽

Functional Connectivity ◽

Autism Spectrum ◽

Spectrum Disorder ◽

Typically Developing ◽

Imaging Data ◽

Functional Magnetic Resonance ◽

Males And Females ◽

Spectrum Disorders

Previous studies have found that individuals with autism spectrum disorders show impairments in mentalizing processes and aberrant brain activity compared with typically developing participants. However, the findings are mainly from male participants and the aberrant effects in autism spectrum disorder females and sex differences are still unclear. To address these issues, this study analyzed intrinsic functional connectivity of mentalizing regions using resting-state functional magnetic resonance imaging data of 48 autism spectrum disorder males and females and 48 typically developing participants in autism brain imaging data exchange. Whole-brain analyses showed that autism spectrum disorder males had hyperconnectivity in functional connectivity of the bilateral temporal-parietal junction, whereas autism spectrum disorder females showed hypoconnectivity in functional connectivity of the medial prefrontal cortex, precuneus, and right temporal-parietal junction. Interaction between sex and autism was found in both short- and long-distance functional connectivity effects, confirming that autism spectrum disorder males showed overconnectivity, while autism spectrum disorder females showed underconnectivity. Furthermore, a regression analysis revealed that in autism spectrum disorder, males and females demonstrated different relations between the functional connectivity effects of the mentalizing regions and the core autism spectrum disorder deficits. These results suggest sex differences in the mentalizing network in autism spectrum disorder individuals. Future work is needed to examine how sex interacts with other factors such as age and the sex differences during mentalizing task performance.

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