Friday, April 19, 2024

Is Autism A Genetic Disorder

Don't Miss

Behaviour Analysis Of Asds

Genetics and Autism Spectrum Disorder Part One

Although now a days knowledge concerning autism is much more prefound, it still surprises due to the diversity of characteristics that patients can show.

Usually, the autistic child has normal physical . However, these children also show an irregular profile of development that is detectable in the first three years of life, being present till adulthood. The Triade of Social Impediments is characterized by a strict and continuous pattern with intelligence levels varying from mental retardation to an extraordinary performance in certain cognitive domains or savant capacities . Although 80% of autistic children show mental retardation, savant capacities can exist, however the global intelligence ratio is low . The difference between mental retardation and autism should be pointed out: The first one shows a uniform development deficit while the last presents an irregular profile, with differentiated degrees of commitment.

The following classification and diagnosis systems allow to distinguish autism from other disorders: International classification of Diseases of the World Health Organization and the Manual of Diagnosis and Statistics of Mental Disorders from the American Academy of Psychiatry . In these systems the term Child Autism was replaced by Autistic Disturbance, officially separating it from Asperger syndrome .

How Is Asd Diagnosed

ASD symptoms can vary greatly from person to person depending on the severity of the disorder. Symptoms may even go unrecognized for young children who have mild ASD or less debilitating handicaps.

Autism spectrum disorder is diagnosed by clinicians based on symptoms, signs, and testing according to the Diagnostic and Statistical Manual of Mental Disorders-V, a guide created by the American Psychiatric Association used to diagnose mental disorders. Children should be screened for developmental delays during periodic checkups and specifically for autism at 18- and 24-month well-child visits.

Very early indicators that require evaluation by an expert include:

  • no babbling or pointing by age 1
  • no single words by age 16 months or two-word phrases by age 2
  • no response to name
  • excessive lining up of toys or objects
  • no smiling or social responsiveness

Later indicators include:

  • impaired ability to make friends with peers
  • impaired ability to initiate or sustain a conversation with others
  • absence or impairment of imaginative and social play
  • repetitive or unusual use of language
  • abnormally intense or focused interest
  • preoccupation with certain objects or subjects
  • inflexible adherence to specific routines or rituals

Plenty Of Genes Involved

Some genetic conditions are simple, and they stem from one unusual item found in one strand of DNA. Autism is much different, and that complexity makes the condition a lot harder to spot.

In January 2020, researchers published the results of a massive study that included:

  • A large study group. More than 35,000 people sent in samples for analysis.
  • ASD data. Of the 35,000 participants, almost 12,000 had autism spectrum disorder.
  • Gene sequencing. Testing methods picked up rare mutations that might stay masked with other methods.

Per the results, more than 102 genes were attached to autism risk. This is a huge number, and researchers suspect that the genes intertwine and intermingle.

Some of them are associated with other developmental delays. Others seem to increase the risk of neurodevelopmental disorders.

The researchers don’t yet know how the genes work, so parents can’t walk into a laboratory and ask for an autism gene screening. There is too much data to look for and a lot we don’t know.

But this study suggests that many genes, working together, could raise autism risks. That data could be helpful as researchers look for ways to treat, and perhaps even cure, ASD.

Also Check: Does James Holzhauer Have Autism

Study Examining Whether Parental Mental Health Concerns Are Related To Caregiving

Research has indicated that parents of children on the autism spectrum are more likely to suffer from a variety of mental health concerns. A 2011 study in the Journal of Developmental and Physical Disabilities examined whether these mental health issues, which can include anxiety, depression and obsessive-compulsive behaviors, are the result of caring for a child with autism or are a genetic factor that may predispose a family to autism.

The study, which included more than 700 parents, found that underlying genetic factors were more likely to be responsible for parents’ mental health issues.

Genetic Testing And Autism Spectrum Disorder

3 Charts

If your child is diagnosed with ASD, the doctor might refer your child for genetic counseling and testing.Genetic testing looks for causes of ASD but cannot be used to diagnose ASD. Some people with ASD have syndromic ASD, meaning that they have other specific features in addition to having ASD, such as looking different from other people in the family or having birth defects. Most people with syndromic ASD have a genetic cause for their ASDexternal icon.

Genetic testing is more likely to find a genetic cause for ASD if

  • Your child or another family member has syndromic ASD
  • A family member has an ASD-related genetic change found through genetic testing or
  • Multiple family members have ASD.

The most commonly ordered test for people with ASD is called a chromosomal microarray . This test looks at chromosomes to see if there are extra or missing parts that could cause ASD. CMA finds a genetic cause in 5% to 14% of people with ASDexternal icon who have the test.

In addition, children with ASD should be checked for genetic disorders that can cause ASD, including the following:

You May Like: How To Make A Visual Schedule For Autism

What Disorders Are Related To Asd

Certain known genetic disorders are associated with an increased risk for autism, including Fragile X syndrome and tuberous sclerosis each of which results from a mutation in a single, but different, gene. Recently, researchers have discovered other genetic mutations in children diagnosed with autism, including some that have not yet been designated as named syndromes. While each of these disorders is rare, in aggregate, they may account for 20 percent or more of all autism cases.

People with ASD also have a higher than average risk of having epilepsy. Children whose language skills regress early in life before age 3 appear to have a risk of developing epilepsy or seizure-like brain activity. About 20 to 30 percent of children with ASD develop epilepsy by the time they reach adulthood. Additionally, people with both ASD and intellectual disability have the greatest risk of developing seizure disorder.

Epigenetic Dysregulation In Autism

Although most of the epigenetic modifications described above are underpinned by genetic mechanisms, the evidence of the contribution of epigenetic dysregulation in autism raises the issue of the role of epigenetic modifications by environmental factors. An example is assisted conception. Indeed, while it was shown that in vitro fertilization and ovulation induction can result in abnormal methylation and dysregulation of imprinted genes, epidemiologic studies on the use of assisted reproductive technology and the risk of autism found conflicting results.

Recommended Reading: Do Autistic Toddlers Dance

Clinical And Therapeutic Implications

In some, but not all, best practice clinical guidelines, genetic tests such as fragile X testing, chromosomal microarray, and karyotype testing are part of the standard medical assessment in a diagnostic evaluation of autism to identify potentially etiologically relevant rare genetic variants . The guidelines vary with respect to whether genetic testing is recommended for all people with autism, or based on particular risk factors, such as ID, seizures, or dysmorphic features. The DSM-5 diagnosis of autism includes a specifier for associated genetic conditions . Although genetic test results may not usually have consequences for treatment changes, the results could inform recurrence risk and provide families with access to information about symptoms and prognosis. In the future, gene therapy, CRISPR/Cas9, and genome editing technologies may lead to the gene-specific design of precision medicine for rare syndromic forms of autism .

Notably, there are important ethical challenges related to clinical translation of advances in genetics, including concerns about discriminatory use, eugenics concerning prenatal genetic testing, and challenges in interpretation and feedback . People with autism and their families are key stakeholders in genetic studies of autism and essential to include in discussions of how genetic testing should be used.

Autism And Genetic Syndromes

Genetics of Autism Spectrum Disorders, Dr. Abha Gupta

Submitted: November 2nd 2010Reviewed: March 22nd 2011Published: August 1st 2011

DOI: 10.5772/19161

  • Erasmus University Medical Centre, RotterdamRadboud University Nijmegen, NijmegenVincent van Gogh Institute, Venray, The Netherlands
  • Jos Egger*

  • Erasmus University Medical Centre, RotterdamRadboud University Nijmegen, NijmegenVincent van Gogh Institute, Venray, The Netherlands
  • Ilse Feenstra*

  • Erasmus University Medical Centre, RotterdamRadboud University Nijmegen, NijmegenVincent van Gogh Institute, Venray, The Netherlands
  • *Address all correspondence to:

    Don’t Miss: Nick Eh 30 Hide And Seek

    Clinical Development And Diagnoses

    Leo Kannerearly infantile autism

    The word autism first took its modern sense in 1938 when Hans Asperger of the Vienna University Hospital adopted Bleuler’s terminology autistic psychopaths in a lecture in German about child psychology. Asperger was investigating an ASD now known as Asperger syndrome, though for various reasons it was not widely recognized as a separate diagnosis until 1981.Leo Kanner of the Johns Hopkins Hospital first used autism in its modern sense in English when he introduced the label early infantile autism in a 1943 report of 11 children with striking behavioral similarities. Almost all the characteristics described in Kanner’s first paper on the subject, notably “autistic aloneness” and “insistence on sameness”, are still regarded as typical of the autistic spectrum of disorders. It is not known whether Kanner derived the term independently of Asperger.

    Kanner’s reuse of autism led to decades of confused terminology like infantile schizophrenia, and child psychiatry’s focus on maternal deprivation led to misconceptions of autism as an infant’s response to “refrigerator mothers“. Starting in the late 1960s autism was established as a separate syndrome.

    Asd Is Diagnosed By Behavior

    According to Frazier, theres no biological test available for autism.

    The condition is clinically diagnosed using behavioral observation such as the ADOS , or for older children and adults, the ADI-R that was used in this study, he said.

    Frazier pointed out that in either case, its important for children diagnosed with autism to have genetic testing, as recommended by the American Academy of Pediatrics , to identify underlying genetic conditions.

    On the other hand, children with genetic conditions can be evaluated for autism and related challenges, he said.

    Even if a child doesnt meet the criteria for a diagnosis of ASD, a developmental evaluation for children with a genetic disorder can lead to identifying other conditions like social communication disorders, behavioral conditions or learning disabilities, and getting necessary supports and services in place that the child needs, Frazier said.

    Recommended Reading: How To Make A Visual Schedule For Autism

    How Is Autism Treated

    There is no cure for ASD. Therapies and behavioral interventions are designed to remedy specific symptoms and can substantially improve those symptoms. The ideal treatment plan coordinates therapies and interventions that meet the specific needs of the individual. Most health care professionals agree that the earlier the intervention, the better.

    Educational/behavioral interventions: Early behavioral/educational interventions have been very successful in many children with ASD. In these interventions therapists use highly structured and intensive skill-oriented training sessions to help children develop social and language skills, such as applied behavioral analysis, which encourages positive behaviors and discourages negative ones. In addition, family counseling for the parents and siblings of children with ASD often helps families cope with the particular challenges of living with a child with ASD.

    Disorders Similar To Autism

    Recessive mutations in autism â the return of hidden ...

    By Andréas RB Deolinda, BA, BSc

    Autism spectrum disorder has a diverse array of markers and traits. So much so that every individual on the autism spectrum experiences a variety of symptoms different to the next person and many ASD symptoms can be found in other disorders similar to autism.

    Autism is categorized by symptoms such as social interaction and social communication difficulties, restricted and repetitive patterns of behavior, interests, or activities as per the Diagnostic and Statistical Manual of Mental Disorders other symptoms include sensory sensitivity and atypical behavior.

    Due to the many different characteristics of autism, some conditions resemble autism spectrum disorders due to similarities in traits. This article aims to provide an overview of autism spectrum disorders and other pervasive developmental disorders that are found to be similar in symptoms, and break down their differences. In addition, it will highlight comorbid disorders that are commonly associated with ASD.

    The article aims to provide parents of autistic children with an understanding of these conditions. It should also be beneficial for parents seeking answers for some symptoms experienced by their children.

    Also Check: How To Improve Sitting Tolerance In Autism

    Which Conditions Resemble Or Can Be Mistaken For Autism

    Now that we have an idea of the benefits of assessment and what they measure, lets look at some conditions which resemble autism.

    Neurodevelopmental disorders include a group of pervasive developmental disorders that include ASD, aspergers syndrome, pervasive developmental disorder not otherwise specified , childhood disintegrative disorder , and Rett disorder. The autism spectrum disorders include autism disorder, aspergers disorder, and PDD. Most of these conditions are genetically linked .

    Article Discussing Current Genetic Research Into Autism

    An article in the scientific journal Trends in Cognitive Sciences discussed a decade’s worth of genetic studies in the area of autism. The article maintained that only 10 to 20 percent of ASD cases could be accounted for using the genes currently identified as related to autism.

    The authors point out that these studies share a common theme: that genetic factors influence neurological pathways. This connection provides a tool for future researchers to determine what accounts for the similarities and differences in various autism spectrum disorders.

    You May Like: What Is The Life Expectancy Of People With Autism

    The Role Of Rare Mutations Versus Common Polymorphisms In Asd

    A series of important findings over the last four years clearly challenges the notion that autism is mainly caused by combinations of common variants by identifying a large number of rare, recurrent, and non-recurrent mutations that lead to ASD. At the same time, whole genome association studies with common variants, while identifying a few loci with very small effect sizes, have not yielded independently replicated results . These rare mutations, mostly in the form of sub-microscopic chromosomal structural variation, called copy number variants , are now known to account for up to 10% of cases of idiopathic autism . Since many of these CNV have large effect sizes and thus are thought sufficient to cause ASD, they are predicted to significantly reduce reproductive fitness. Consistent with this, these causal CNV are often not transmitted from the parent, but instead occur de novo in the germline . However, in some cases, such as CNV at 16p11 and 15q11-13, the CNV are transmitted from an unaffected parent to cause the disorder in an offspring . The genetic or epigenetic mechanism for the reduced penetrance for ASD in the mutation-carrying parent is not known. However, it is also very likely that the parent carriers of such CNV have more subtle neuropsychiatric or cognitive phenotypes that have not yet been systematically identified.

    Challenges And Future Perspectives

    Genetics of Autism Spectrum Disorders

    The field of imaging genetics has exponentially grown in recent decades from its candidate gene studies to large-scale longitudinal studies, cross-modal investigations, and translational animal models of various psychiatric disorders. In addition, imaging genetics has begun integrating transcriptomic data and analytical methods for assessing pathway enrichment, such as the score system for pathway regulation. Of addition to translational animal research and pharmacological intervention in vitro and in vivo, imaging genetics can also provide an insight into various behavioral and genetic factors that contribute to the risk of ASDs.

    One of the challenges facing imaging genetics is the conceptualization of endophenotypes, which states that endophenotypes are heritable and associated with psychiatric disorders and may impede research on brain-based associations by limiting imaging genetic research to genes previously associated with a psychiatric disorder. It is important to properly replicate the studies, particularly those with false-positive results, to address the impact of a genetic variation in a disease, and this problem can be solved by correcting genome-wide associations with large sample size imaging phenotypes.

    Read Also: Is Dr Shaun Murphy Really Autistic

    Diagnostic Models Based On Mr

    MRI-based diagnostic models are used for the behavioral assessment of autistic patients. These diagnostic model studies involve three steps, including extraction of properties from MR images, construction of diagnostic model using statistical models followed by evaluation and validation by researchers. Several studies have focussed on MRI-based diagnostic models for the detection and classification of ASD,. Diagnostic model performance is strongly influenced by types of entities selected as components of the model. For example, a study showed the comparison of diagnostic models based on regional thickness derived from surface morphometry with diagnostic models based on volumetric morphometry involving four different classification methods and classification based on thickness was found to be more efficient and predictive of ASD compared to classification based on volume. rsfMRI pipelines have been used to extract predictive biomarkers in autism by constructing participant-specific connectomes and then comparing these connectomes across participants to learn connectivity patterns that may identify ASD individuals. The results suggested that rsfMRI data collected from different sites could reveal robust functional connectivity biomarkers of ASD.

    Early Diagnosis Is Critical

    Early diagnosis for children with autism is critical because the sooner that child can get the support they need, the better their chances for positive outcomes as they grow, Tom Frazier, PhD, chief science officer at Autism Speaks, said in an emailed statement.

    Frazier emphasized that formal autism diagnosis can open the door to certain treatments.

    He also said that children with specific developmental delays like speech or motor issues should be referred for services immediately without waiting for an autism diagnosis.

    This ensures that children can continue to make progress and develop early skills that help them reach their full potential, he said.

    Don’t Miss: What Is The Life Expectancy Of People With Autism

    More articles

    Popular Articles