National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Autism spectrum disorder

Not a rare disease Not a rare disease
Other Names:
ASD
Categories:
Autism spectrum disorder (ASD) is a condition that affects the development of social and communication skills. It includes features of four conditions which were once thought to be separate syndromes - autistic disorder, Asperger syndrome, childhood disintegrative disorder, and pervasive developmental disorder. Signs and symptoms often become apparent in the first 2-3 years of life and vary significantly from person to person. Common symptoms shared by people with ASD include restrictive and repetitive behaviors, social impairment and communication difficulties. The underlying cause of ASD is generally unknown and it is likely that a variety of factors contribute to the development of the condition. ASD appears to run in some families, suggesting that genetics may play a role in some cases. Although there is no cure for ASD, treatment is available that significantly improves the long-term outlook for affected people. Treatment often includes a combination of techniques such as medications, occupational therapy, speech therapy and physical therapy.[1][2][3]
Last updated: 12/1/2016
The signs and symptoms of autism spectrum disorder generally become apparent in the first two to three years of life and vary significantly from person to person. In general, common features shared by people with ASD include restrictive and repetitive behaviors, social impairment and communication difficulties.[3]

Restrictive and repetitive behaviors:[2][3][1][4]
  • Sensitivity to changes in routine
  • Repetitive body movements
  • Overly focused interests, such as with moving objects or parts of objects
  • Lasting, intense interests in certain topics, such as numbers, details, or facts.
Social impairment:[2][3][1][4]
  • Difficulty making friends
  • Unable to play interactive games
  • No response to eye contact or smiles, or may avoid eye contact
  • Prefers to be alone rather than with others
  • Unable to show empathy
Communication difficulties:[2][3][1][4]
  • Develops language slowly or not at all
  • Trouble starting and maintaining a conversation
  • Uses gestures instead of words
  • Speaks at length about a favorite subject without noticing that others are not interested or without giving others a chance to respond
  • Uses words that seem odd, out of place, or have a special meaning known only to those familiar with that person's way of communicating
  • Facial expressions, movements, and gestures may not match what is being said
  • Unusual tone of voice that may sound sing-song or flat and robot-like
  • Doesn't point to show other people objects (normally occurs in the first 14 months of life)
  • Repeats words or memorized passages, such as commercials

Last updated: 12/5/2016

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

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Medical Terms Other Names
Learn More:
HPO ID
30%-79% of people have these symptoms
EEG abnormality 0002353
Increased serum serotonin 0003144
Seizure 0001250
Percent of people who have these symptoms is not available through HPO
Autism 0000717
Childhood onset
Symptoms begin in childhood
0011463
Delayed speech and language development
Deficiency of speech development
Delayed language development
Delayed speech
Delayed speech acquisition
Delayed speech development
Impaired speech and language development
Impaired speech development
Language delay
Language delayed
Language development deficit
Late-onset speech development
Poor language development
Speech and language delay
Speech and language difficulties
Speech delay
[ more ] 		0000750
Impaired ability to form peer relationships 0000728
Impaired use of nonverbal behaviors
Impaired use of nonverbal behaviours
0000758
Inflexible adherence to routines or rituals 0000732
Intellectual disability
Mental deficiency
Mental retardation
Mental retardation, nonspecific
Mental-retardation
[ more ] 		0001249
Lack of spontaneous play 0000721
Multifactorial inheritance 0001426
Restrictive behavior 0000723
Sporadic
No previous family history
0003745
Stereotypy
Repetitive movements
Repetitive or self-injurious behavior
[ more ] 		0000733
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Last updated: 7/1/2020
The underlying cause of autism spectrum disorder (ASD) is generally unknown. Scientists suspect that it is a multifactorial condition, meaning that a variety of factors (both genetic and environmental) likely contribute to the development of the condition.[1][2]

Known risk factors for ASD include:[4][1][2][3]
  • Male gender
  • Having a sibling with ASD
  • Having older parents (a mother who is 35 or older, and/or a father who is 40 or older when the baby is born)
  • Having certain genetic conditions (including Down syndrome, fragile X syndrome, and tuberous sclerosis)
  • Exposure to certain prescriptive medications during pregnancy (such as valproic acid, thalidomide)
Of note, no scientific evidence for a relationship between vaccines and autism has been identified.[1]
Last updated: 12/2/2016
A diagnosis of autism spectrum disorder (ASD) may be suspected in young children who are not meeting typical social and language milestones. Although medical tests (i.e. blood tests, imaging studies, a hearing test) may be ordered to rule out other conditions that can be associated with similar features, there is not specific test available to confirm a diagnosis of ASD. Instead, a diagnosis is often based on guidelines from a medical book called Diagnostic and Statistical Manual of Mental Disorders. A team of specialists with knowledge of standardized testing of autism may evaluate the following abilities to support a diagnosis:[1][2][5]
  • Communication
  • Language
  • Motor skills
  • Speech
  • Success in school
  • Thinking abilities
Last updated: 12/6/2016
Although there is currently no cure for autism spectrum disorder (ASD), available treatment programs significantly improve the outlook for most affected children. Treatment plans may include a combination of the following techniques, including:[1][2]
For more information about the treatment and management of ASD please visit the MedlinePlus or Medscape Reference websites.
Last updated: 12/6/2016

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • The Autism Speaks organization has information about the many opportunities that are available for families who want to participate in autism research. Click on the link to learn more about the way families can participate.
  • The Centers for Mendelian Genomics program is working to discover the causes of rare genetic disorders. For more information about applying to the research study, please visit their website.
  • ClinicalTrials.gov lists trials that are related to Autism spectrum disorder. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.
  • The National Database for Autism Research (NDAR) is a collaborative biomedical informatics system being created by the National Institute of Health (NIH) to provide a national resource to support and accelerate research in autism.
  • The Investigation of Genetic Exome Research (TIGER) study is enrolling research participants ages 4 to adult to participate in a study exploring how specific genetic events may contribute to Autism Spectrum Disorders and related developmental disorders. Click on the link for a list of gene mutations currently being studied. If you are interested in learning more, please contact the study coordinator at 206-616-2889 or rablab@uw.edu.

Patient Registry

  • A registry supports research by collecting of information about patients that share something in common, such as being diagnosed with Autism spectrum disorder. The type of data collected can vary from registry to registry and is based on the goals and purpose of that registry. Some registries collect contact information while others collect more detailed medical information. Learn more about registries.

    Registries for Autism spectrum disorder:
    The Waisman Center
    Simons SearchLight
     

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.

Education Resources

  • The Genetics Education Materials for School Success (GEMSS) aims to assure that all children with genetic health conditions succeed in school-life. Their Web site offers general and condition-specific education resources to help teachers and parents better understand the needs of students who have genetic conditions.

Community Resources

  • The Job Accommodation Network (JAN) has information on workplace accommodations and disability employment issues related to this condition. JAN is a service of the Office of Disability Employment Policy in the U.S. Department of Labor.

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • The Autism Society of America is a support organization for individuals and families affected by autism spectrum disorders. Click on the link to view their information page on ASD.
  • You can obtain information on this topic from the Centers for Disease Control and Prevention (CDC). The CDC is recognized as the lead federal agency for developing and applying disease prevention and control, environmental health, and health promotion and education activities designed to improve the health of the people of the United States.
  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
  • The Merck Manuals Online Medical Library provides information on this condition for patients and caregivers. 
  • The National Human Genome Research Institute (NHGRI) website has an information page on this topic. NHGRI is part of the National Institutes of Health and supports research on the structure and function of the human genome and its role in health and disease.
  • The National Institute of Mental Health (NIMH) has information on this topic. NIMH is part of the National Institutes of Health and is dedicated to understanding, treating, and preventing mental illnesses.
  • The National Institute of Neurological Disorders and Stroke (NINDS) collects and disseminates research information related to neurological disorders. Click on the link to view information on this topic.

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Autism spectrum disorder. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.

  1. Autism Spectrum Disorder. MedlinePlus. May 2016; https://medlineplus.gov/ency/article/001526.htm.
  2. James Robert Brasic, MD, MPH. Autism. Medscape Reference. November 2016; http://emedicine.medscape.com/article/912781-overview.
  3. Autism Spectrum Disorder. National Institute of Mental Health. October 2016; https://www.nimh.nih.gov/health/topics/autism-spectrum-disorders-asd/index.shtml.
  4. Facts About ASD. Centers for Disease Control and Prevention. March 2016; https://www.cdc.gov/ncbddd/autism/facts.html.
  5. Learning About Autism. National Human Genome Research Institute. November 2012; https://www.genome.gov/25522099.