Autistic Siblings Not Necessarily Similar

Nature Medicine - siblings studyIn a recent report published by Nature Medicine, scientists have found that most siblings with autism do not share the same genetic risk factors and are as distinct in their behaviors as any brothers and sisters – which is a surprise to many.

As discussed in this New York Times article, scientists analyzed genetic material from 85 families using an approach called whole-genome sequencing. And they found that 30% of the 85 sibling pairs in the study shared the same mutation, while about 70% did not.

By having different mutations, this means that the impact, and symptoms, of autism can vary greatly, even among with closest of relatives. (One family is discussed in the NYT article as an example – two brothers sharing an autism diagnosis, one will approach strangers, the other is much more shy; one loves computers, the other doesn’t; one brother is continuously on the move, while the other usually parks himself in the same place.)

The saying of “if you know one person with autism, then you know one person with autism” really holds true, even when it comes to individual families.

Read more about the study here.

Lynsey, Community Manager 

100+ Genes Tied to Autism (New Study)

cover_natureSome new research that came out is getting a lot of attention. As we are still without a known cause of autism, this particular research could potentially prove to be a step closer to having a better understanding of what may cause autism.

Two studies were published in Nature that showed dozens of sets of genes are closely connected to the development of autism. As discussed in this article, the research claims that 60 genes are within a ‘high-confidence” threshold—meaning that mutations in those genes are 90% likely to increase the risk of autism. (Previously only 11 genes had been identified with the ‘high-confidence’ threshold.)

It went on to show that these genes appear to be clustering around three sets of biological functions—(1) the development of synapses (which are responsible for communication among nerves); (2) the creation of genetic instructions; and, (3) DNA packaging within cells.

With environmental factors being a possible theory of what may cause autism, this research may now steer scientists more toward genetics.

As with any new research and findings, more investigation is needed – but their initial discovery is very compelling.

Read more about this study here.

Lynsey, Community Manager

Environment Equally Important as Genes (Study)

It’s a question that many parents ask – ‘If I have a child with autism, what is the risk my next child will have autism too?’ This question is what prompted the largest analysis to date that looked at how autism runs in families.

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And what researchers found out was that environmental factors are

more important than previously thought –

and, based on their findings, they are actually as big of factors as genes. Their research, which was published in the Journal of the American Medical Association (JAMA), suggests that heritability is 50% of the story, while the other half could be related to environmental elements such as birth complications, socio-economic status or parental lifestyle.

They found that a brother or sister with autism are 10 times more likely to develop the disorder and 3 times more likely if they have a half-brother or sister with autism. To read more about this study, check out this article.

Lynsey, Community Manager