Can autism occur in twins?

Is it common for twins to have autism?

The researchers determined a 96% chance that if one twin has ASD, the other has it, too. However, symptom scores varied greatly between twins diagnosed with ASD. The researchers estimated that genetic factors contributed to only 9% of the cause of trait variation among these twins.

Why is autism more common in twins?

Studies in twins have shown that autism has genetic origins: A child is more likely to have autism if his or her sibling or twin also has the disorder. But there is also evidence that factors other than genetics, collectively referred to as ‘the environment,’ play a role.

Are twins more likely to have disabilities?

A number of studies have shown that, even among children of similar birth weight and gestational age, twins are more likely to suffer from the disorder.

What are the signs of autism?

At any age

  • Loss of previously acquired speech, babbling or social skills.
  • Avoidance of eye contact.
  • Persistent preference for solitude.
  • Difficulty understanding other people’s feelings.
  • Delayed language development.
  • Persistent repetition of words or phrases (echolalia)
  • Resistance to minor changes in routine or surroundings.
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What percentage of twins are autistic?

Based on data from 192 pairs of twins, the new study found a concordance rate for autism spectrum disorders of 77 percent among identical twin boys and 31 percent among fraternal twin boys.

What is autism caused by?

There is no known single cause for autism spectrum disorder, but it is generally accepted that it is caused by abnormalities in brain structure or function. Brain scans show differences in the shape and structure of the brain in children with autism compared to in neurotypical children.

What’s the signs of autism in a child?

Signs of autism in children

  • not responding to their name.
  • avoiding eye contact.
  • not smiling when you smile at them.
  • getting very upset if they do not like a certain taste, smell or sound.
  • repetitive movements, such as flapping their hands, flicking their fingers or rocking their body.
  • not talking as much as other children.

Can one twin have Aspergers?

In identical twin sets where both children had some form of ASD, it was very unusual for one to have Asperger’s and the other to have autism or PDD-NOS. In other words, when one identical twin had Asperger’s, the other usually, did, too.

What are the disadvantages of having twins?

With twins, you’re at greater risk for:

  • Premature birth. Twins are born prematurely more than half the time. …
  • Low birth weight (LBW). More than half of twins are born with LBW, weighing less than 5 1/2 pounds. …
  • Twin-twin transfusion syndrome (TTTS).

Do twins have emotional problems?

Parents’ reported proportions of probable behavioural/emotional disorders did not differ between the twin and singleton girls, but among the twin boys there was a nonsignificant trend of being more often probably disturbed. Twins were reported to be less disturbed than singletons according to the teachers’ assessments.

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