Zeroing In On The Genetics Of Autism
Some evidence that genetics plays a role in autism and ASD is provided by research on twins. According to the CDC, if one identical twin has autism, there’s a 75% chance the other twin will be affected, too. If a fraternal twin is affected, the other twin has a 3% chance of having autism.
Parents who give birth to a child with ASD have up to an 8% chance of having another child who is also affected, the CDC estimates.
Many U.S. couples have delayed childbearing, and the older ages of both the mother and the father have been linked with a higher risk of having children with ASD, according to a report in the journal Pediatrics. With age could come increased risk for genetic mutations or other genetic problems.
Specific genetic problems help explain only a small percentage of autism cases so far. “We know that major chromosomal abnormalities are identified in about 5% of ASD,” says Milunsky of Boston University. “We know that Fragile X syndrome is responsible for about 3%.” Fragile X syndrome, a family of genetic conditions, is the most common cause of inherited mental impairment, and also the most common known cause of autism or autism-like behaviors.
“Hot spots” of genetic instability may play a role, researchers say. For instance, a team of researchers reported in The New England Journal of Medicine that duplications and deletions on a specific chromosome seem to be associated with some cases of autism.
But genetics is not the whole story, he and other experts say.
Policy For Autism Diagnosis Begins Requiring Screening For All Children Revealing More Cases
The American Academy of Pediatrics introduced a policy recommending pediatricians screen for autism beginning at 18 months and again at 24 months. This earlier screening, happening more frequently, adds to ASD prevalence. The AAP policy is only a recommendation with the final call relegated to states and pediatricians. The AAP also doesnt require a specific tool for ASD screening. These two factors reveal vulnerabilities in the accuracy of ASD diagnosis data.
Is Synaesthesia More Common In Autism
Beyond such single-case reports of synaesthesia in autism, it has been proposed that synaesthesia may be common in autism . The idea has tentative indirect support from two different lines of investigation. First, a molecular genetic study of families with auditory-visual synaesthesia found linkage to an area on chromosome 2,
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Why Autism Is More Common In Men
Research has proven that autism is constantly spreading and that this rate is increasing day by day. It has also been found more in males when researching the sex of a large proportion of autistic patients. Why autism is more common in men, can you continue to read the answers to the questions as if there is a specific reason for this.
Why Is Autism More Common For Males
In newborn babies, girls have shown to be more stimulated by peoples faces and boys more stimulated by cot mobiles. This stage of development is significant because as they are newborn they are not affected by gender conditioning. Children with Autism show more pronounced results in similar tests.
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Why Is Autism So Much More Common
Finally, as autism came to be better described and understood, it lost many of the social stigmas of other childhood psychiatric conditions. Because the disorder exists along a spectrum that can be accommodated in many circumstances and because applied behavior analysis offers effective treatment for many patients, an autism diagnosis has become less onerous over the years.
How Autism Rates Have Increased
If the Facebook post meant “increase in autism rates,” a “30,000% increase in autism” would require the rate of prevalence to be 300 times what it was 50 years ago. Autism rates have increased immensely in the last half-century, though not at the rate the post states.
In the 1960s, researchers estimated that 0.04% of European children, or roughly 1 in 2,500 children, had autism, according to HuffPost. Currently, 1.85% of all American children, or 1 in 54, are estimated to have autism, according to the CDC’s Autism and Developmental Disabilities Monitoring Network. A comparison of the 1966 estimate and the 2020 estimate shows the prevalence estimate increased 45-fold in that time period.
The widely publicized increase in diagnoses has become a cause for concern among parents and public health experts. However, it does not mean that a child today is 45 times more likely to truly have ASD and its symptoms than a child 50 years ago was. Many studies confirm the increase is due not just to true biology, but rather broader diagnostic criteria and ASD awareness and resources.
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Is Autism Really Becoming More Common
Posted March 13, 2012
Last year I participated in the Autism Speaks-CDC workshop on evaluating changes in the prevalence of autism. Now that the CDC has published the meeting summary, I’d like to offer a few thoughts on the discussions and findings that came out of this meeting.
I wish I could say we had a solid conclusive finding, but we didn’t. If anything, we emerged with more questions than we had when we started. That said, the meeting did produce worthwhile results that will help shape plans and directions for the work ahead of us.
We talked about studies that found “pockets of autism” in particular places and demographic groups. For example, we discussed a study that found autism was more common near interstate highways in California. Does this suggest that traffic is contributing to an overall increase in autism? We don’t know, because it’s unclear whether this situation is new or long standing.
Even when a situation of high prevalence is obviously new – the “Geek enclaves” around tech companies being a good example – we don’t know if this is contributing to an overall increase, or simply concentrating autistic people from a wide area into a single spot.
Many researchers in many fields are trying to understand the increase in these conditions. Could some common factors be contributing to all of these “epidemics,” including autism? It’s certainly possible.
Genetic And Gender Differences Associated With Autism
One theory about why autism appears to be more common in boys suggests that the disorder stems from one or more defective genes on the X chromosome. This genetic theory, proposed by D.H. Skuse, is based on the idea that boys, who have only one X chromosome, are more susceptible to autism because they do not have the protection of a second normal X chromosome as found in girls. Other genetic-based autism theories examine the possibility that boys are more susceptible to the disorder due to the mutations of several genes located on different non-sex chromosomes.
Some scientists and researchers speculate that the structure of the male brain, which tends to be wired in a technical rather than an emotional sense, is more conducive to the displaying of externalized autistic traits. Girls who have an autism spectrum disorder may be better able to conceal their condition due to a higher development of the brain centers that regulate concepts such as social awareness and the capacity to empathize with others.
Presently, the greater incidence of autism in boys cannot be fully explained by any conclusive research findings on the part of scientists or mental health professionals. It is hoped that continued studies on this topic will provide insight as to whether autism can be definitively linked to gender differences.
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Zeroing In On Environmental Triggers
A variety of environmental triggers is under investigation as a cause or contributing factor to the development of ASD, especially in a genetically vulnerable child.
Exposure to pesticides during pregnancy may boost risk. In a study published in Environmental Health Perspectives, researchers compared 465 children diagnosed with ASD with nearly 7,000 children without the diagnosis, noting whether the mothers lived near agricultural areas using pesticides.
The risk of having ASD increased with the poundage of pesticides applied and with the proximity of the women’s homes to the fields.
Besides pesticide exposure, exposure to organic pollutants that have built up in the environment are another area of concern, says Pessah of UC Davis. For instance, polychlorinated biphenyls or PCBs, substances previously found in electrical equipment, fluorescent lighting and other products, are no longer produced in the U.S. but linger in the environment, he says. “Particular types of PCBs are developmental neurotoxins,” he says.
Another toxin to the brain is mercury in its organic form. But according to a report published in Pediatrics, there is no evidence that children with autism in the U.S. have increased mercury concentrations or environmental exposures. Though many parents of children with ASD believe their child’s condition was caused by vaccines that used to contain thimerosal , the Institute of Medicine concludes there is no causal association.
Asd Prevalence In Males And Females
From the first published descriptions of autism, it has been a male-typical disorder: 8 of the 11 cases described by Kanner , and all 4 cases described by Asperger , were male. Prevalence surveys conducted since have reported a range of male biases from 1.33:1 male:female to 15.7:1 , and a commonly referenced consensus ratio of ~4:1. Intelligence level affects this sex ratio: males are substantially over-represented among high-functioning cases, and males and females are more equally represented among cases with severe intellectual disability a 1999 review reported median sex ratios of 6:1 among normal-functioning subjects and 1.7:1 among cases with moderate to severe ID .
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Diagnosis Of Autism: What We Do Know
Autistic children benefit from early diagnosis, preferably in the first two years of life. Early diagnosis allows behavioral therapy or other treatments to begin early when it seems to be most effective. If you are concerned about your child, talk to your doctor about a referral to see a specialist who can help determine if follow-up is needed. Signs of autism may include symptoms such as:
- no babbling or pointing by age 1
- no single words by 16 months or two-word phrases by age 2
- no response to name
- loss of language or social skills
- poor eye contact
Cognitive Functioning Among Children With Autism
Autism is not a learning disability, but it can affect cognitive function. Some children on the autism spectrum have delays in speech or learning, while others do not. Because it is a spectrum disorder, these delays can range from mild to severe.
- One-third of children with autism were classified as having an intellectual disability .
- 7% more girls than boys were identified to have an intellectual disability with autism .
- 24% of children with autism had an IQ in a borderline range .
- Black and Hispanic children were more likely than white children to have an intellectual disability with autism.
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Do More Children Have Autism Now Than Before
This article was originally posted on The Conversation on 5 December, 2011.
273% Increase in Autism and We Dont Know Why! Thursday, April 15, 1999, Los Angeles Times.
The rising prevalence of autism is a story destined to achieve headlines, take up column inches and even bump MasterChef from the top of the water-cooler gossip list. The headline above, which appeared in the influential Los Angeles Times, is perhaps the one that started off the frenzy of intrigue.
So, is there a rise in the number of children with autism? And if so, what is causing it?
The first question is by far the easier. Yes, there has most certainly been a steady rise in the incidence and prevalence of autism during the past half-a-century.
The finding is well-replicated and has been observed in every country that has an appropriate data source to tap.
The first survey was conducted in the 1960s and produced a prevalence estimate of one individual with autism in every 2,500 people or 0.04% of the population. When I first started my research in this area in the early 2000s, the oft-quoted figure was one in every 250 people .
In the last decade, studies have seemed to continually outdo each other with higher and higher prevalence figures, ranging from the 2005 Australian figure of one in every 160 people , to a recent South Korean study, which found an astonishingly high rate of one in every 38 people .
Conceptual change
Diagnostic substitution
Methodological differences
Why Is Autism More Common Now
The prevalence of autism in the United States has risen steadily since researchers first began tracking it in 2000. The rise in the rate has sparked fears of an autism ‘epidemic. ‘ But experts say the bulk of the increase stems from a growing awareness of autism and changes to the condition’s diagnostic criteria.2017. 3. 2.
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Clinicians Lean Into Asd Diagnoses For Access To Specialized Services
As awareness of ASD grows, so do specialized services. Prevalence of ASD is affected by this growing scaffolding of ASD-specific support, accessed via a professionals reported diagnosis. Its been found that clinicians are more likely to give an ASD diagnosis in order to access specialized services for families in need. Previously undiagnosed borderline cases now tip into an ASD diagnosis, therefore boosting prevalence. It can be argued that, as of 2013, these borderline cases were already included in the broader ASD definition laid out in the DSM and therefore would have been diagnosed anyway.
Some States Have Fewer Than 10 Children With Asd For Every 1000 Residents While Others Have 30 Kids Or More
It is, therefore, possible that autism has grown more prevalent due to people delaying parenthood at increasing rates, although more research is necessary. Autism spectrum disorder is a neurodevelopmental condition that creates difficulties in social interacti. The world is becoming more aware of autism with every passing year, thanks in large part to the many organizations that have appeared to help spread new research finds more children with autism. It gives us a more holistic picture of the increased rates across the adhd is the most common mental health condition in people with autism, occurring in 28 percent. I am 35 years old and 24 weeks pregnant. But doctors can’t find out, during your pregnancy, if your baby will have autism. Autistic individuals might have intense interests in one or two subjects , and when harnessed, these interests can be a great strength. Autism is far better understood now than it was in the past. Autism is characterized as impairments in social interaction, communication and unusual behavior and interests. But now we know that isn’t the case. Although no studies show a link between geography and having autism, these variations might indicate that some communities are more. For example, for autism i researched what to look for and then all possible therapies and any providers near my home. Boys are four times as likely to have autism than girls, although there doesn’t seem to be a solid explanation as to why.
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Is Adhd The Same As Aspergers
What to know about Asperger’s syndrome and ADHD. Asperger’s syndrome and ADHD are two conditions that both involve brain development. They tend to develop early in life and may cause some similar behavior traits. The medical community, as of 2013, no longer diagnose Asperger’s syndrome as a separate condition.2019. 6. 17.
Findings Highlight The Need For Sex
Boys are four times more likely than girls to be diagnosed with autism spectrum disorder , yet a growing body of research shows that the condition is more common in girls than previously thought, strongly suggesting that new methods are required to diagnose the disorder at younger ages.
A new study from Childrens Hospital of Philadelphia examined differences in the way girls and boys on the autism spectrum used certain types of words during storytelling. This study found that autistic girls used significantly more cognitive process words such as think and know than autistic boys, despite comparable autism symptom severity. The results were recently published in the journal Molecular Autism.
The authors suggest that identifying differences like these opens the door to making sure girls with ASD receive the diagnosis and support they need to achieve the best possible quality of life.
A misdiagnosis means many girls do not receive early intervention and that standard interventions may not be appropriate for meeting girls unique needs. Many autistic women are not diagnosed until they are adults and report significant social challenges and a profound sense of being different from their typically developing peers.
This study was supported by the Autism Science Foundation, the Eagles Charitable Trust, the McMorris Family Foundation, the Allerton Foundation, and a National Institute of Child Health and Human Development grant 5U54HD086984-03.
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Is Autism More Prevalent In Military Families
Military sources indicate that more than 20,000 military dependents, the majority of them children, have some form of autism.
Video answer: Why do people get autism?
9 other answers
Finally, as autism came to be better described and understood, it lost many of the social stigmas of other childhood psychiatric conditions. Because the disorder exists along a spectrum that can be accommodated in many circumstances and because applied behavior analysis offers effective treatment for many patients, an autism diagnosis has become less onerous over the years.
Autism and related conditions seem to run in families if one identical twin is diagnosed with autism, the other twin has a much higher chance of also having autism. We also know that children who are born prematurely have a greater chance of being autistic, and children with older fathers are at slightly higher risk of autism.
Children in families with a history of brain conditions are at increased odds of being autistic, a large study in Sweden suggests 1. The more closely related the family members with these conditions, the greater the childs chances of having autism. Other studies have reported similar trends: A childs odds of having autism increase if she …
Since autism likely involves complex interactions between many different genes and other factors, common genetic predisposing factors are likely more influential in families with multiple affected members, explained Levitt.