New Gene Variants Linked To Autism DiscoveredMain Category: Autism
Also Included In: Genetics
Article Date: 16 Jan 2013
Twenty-five extra gene variants that occur in some people with an ASD (autism spectrum disorder) have been discovered by genetics scientists from The Children's Hospital of Philadelphia, the University of Utah, and Lineagen Inc. (a biotech company).
The research team, led by Hakon Hakonarson, MD, PhD, explained in the journal PLOS ONE that they identified 25 additional copy number variants (CNVs) that occur in some people with autism. CNVs are duplicate or missing stretches of DNA.
They describe these copy number variants as individually rare, but of "high impact", meaning that each one has a strong effect in increasing a person's risk for autism.
Dr. Hakonarson said:
"Many of these gene variants may serve as valuable predictive markers. If so, they may become part of a clinical test that will help evaluate whether a child has an autism spectrum disorder."
Scientists from the Seaver Autism Center at Icahn School of Medicine at Mount Sinai said that there are hundreds of mutated genes linked to ASDs.
Study builds on previous genetic research on ASDThe authors wrote that their latest study had built on and extended previous gene research carried out by Dr. Hakonarson and other scientists who specialize in ASDs.
In this study, the team initially analyzed the DNA of 55 people from families in Utah with multiple members who had been diagnosed with ASDs. The data from high-risk families had been collected by Mark Leppert, PhD. They identified 153 CNVs as potentially linked to autism.
The team wanted to look at these CNVs in a broader ASD population. They custom-designed a DNA array with probes for all 153 CNVs, as well as an additional 185 CNVs which had been linked to autism in previous studies. They gathered and examined all the data to determine how common all the CNVs were in 3,000 people with an ASD and 6,000 control subjects previously gathered in studies carried out at The Children's Hospital of Philadelphia.
The researchers found that:
"These high-impact variants could be most useful in advising parents who already have one child with an ASD. If a second child has delays in reaching developmental milestones, testing for these CNVs could help predict whether that child is also likely to develop an ASD."
The newly identified CNVs need to be added to the ones already in existence in commercially available diagnostic arrays.
Hakonarson said that the CNVs identified in this study occur in genes that are involved in signaling pathways and neuronal development. This reinforces similar findings by Hakonarson and team in their genomic research that was published in 2009.
Hakonarson said "Many of these gene pathways active in ASDs overlap with those in other nervous system disorders, such as schizophrenia and epilepsy. At the same time, our results are consistent with other studies suggesting that many different biological pathways, when disrupted, can lead to ASDs."
The authors concluded:
"Taken together, these data provide strong support for the existence and application of high-impact CNVs in the clinical genetic evaluation of children with ASD."
What is Autism? What is Autism Spectrum Disorder (ASD)?ASD stands for Autism Spectrum Disorder or Autistic Spectrum Disorder. Autism and ASD are commonly used interchangeably. ASDs are a number of developmental disabilities which are the result of a brain abnormality. An individual with an ASD generally has problems with social interaction and communication skills.
Autism is referred to as a complex developmental disability. According to experts, Autism signs and symptoms appear during the first three years of life.
An individual with ASD prefers to stick to a set of behaviors and does not welcome any major (and some minor) changes to their daily routine. Friends and relatives often find that if the person knows in advance that a change is coming, and they have time to prepare or adjust for it, their resistance is much less.
Autism is a wide-spectrum disorder - in other words, each person with an ASD will be affected in a unique way, no two people with autism have exactly the same symptoms. Apart from experiencing a wide combination of signs, some will have mild symptoms while others have more severe ones.
Below are some of the signs and symptoms that exist in people with ASD:
An article published in the Journal of Child Psychology and Psychiatry found that some children outgrow their autism.
Written by Christian Nordqvist
Copyright: MediLexicon International Ltd
Original article posted on Medical News Today.
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