New light on genetics of autism

September 14, 2012

The genetics of autism is complex and possibly influenced by mutations with very large effects. EU genomics research has found more candidate genes that increase susceptibility to the condition.

The EU 'Using European and international populations to identify susceptibility loci' (Autism Molgen) project has completed a comprehensive study of European patients with (ASDs). The study group consisted of around 100 multiplex families where two or more individuals are affected and more than 370 simplex families where one member of the family has an ASD.

The benefit of advanced genomic techniques was used to study the involvement of both previously identified associated genes as well as new candidate alleles. Molecular genetics techniques included linkage studies, association studies and mutation screening.

Using linkage studies to help refine the position of important loci and help identify possible new , logarithm of the odds (LOD) scores were applied to linkage data. A positive score indicating the presence of linkage was achieved for the long arm of chromosome 2, (2q), confirming the importance of this region in ASDs.

Two new candidate genes were identified among (SNPs) using the transmission disequilibrium test (TDT) to test presence of linkage between a marker and a trait. Additional association studies using a further 37 genes revealed a further 5 key genes susceptibility for further study.

Recent research has reported that may play a large role in predisposition to ASDs. A key example is in the case of neuroligins – alterations in genes encoding neuroligins are implicated in autism and other cognitive disorders. Neuroligins are involved in the healthy functioning of synapses. Rare variants with possible functional effects were identified. These included non-synonymous changes altering the position of an amino acid in a protein, stop codon mutations that shorten a protein and splice site mutations that can result in aberrant products. All types of mutation were found both in genes associated with ASD and in other plausible candidates.

Comprehensive genetic data amassed by Autism Molgen has positively identified new susceptibility alleles for ASDs. Future research can focus on functional studies for the genes involved. Given that the incidence of ASDs is reportedly rising by the decade, the project research can contribute to the elucidation of this highly complex condition.

Explore further: Further support for a role of synaptic proteins in autism spectrum disorders

Related Stories

Further support for a role of synaptic proteins in autism spectrum disorders

February 9, 2012
A new study combines genetic and neurobiological approaches to confirm that synaptic mutations increase the risk of autism spectrum disorders (ASDs). It also highlights a role for modifier genes in these disorders. Published ...

Mutations in autism susceptibility gene increase risk in boys

July 12, 2012
Researchers at Emory University School of Medicine have identified five rare mutations in a single gene that appear to increase the chances that a boy will develop an autism spectrum disorder (ASD).

Study explains functional links between autism and genes

June 21, 2012
A pioneering report of genome-wide gene expression in autism spectrum disorders (ASDs) finds genetic changes that help explain why one person has an ASD and another does not. The study, published by Cell Press on June 21 ...

Mutations in 3 genes linked to autism spectrum disorders

April 4, 2012
Mutations in three new genes have been linked to autism, according to new studies including one with investigators at Mount Sinai School of Medicine. All three studies include lead investigators of the Autism Sequencing Consortium ...

Recommended for you

Video game improves balance in youth with autism

November 21, 2017
Playing a video game that rewards participants for holding various "ninja" poses could help children and youth with autism spectrum disorder (ASD) improve their balance, according to a recent study in the Journal of Autism ...

Potential new autism drug shows promise in mice

November 14, 2017
Scientists have performed a successful test of a possible new drug in a mouse model of an autism disorder. The candidate drug, called NitroSynapsin, largely corrected electrical, behavioral and brain abnormalities in the ...

Relational factors in music therapy can contribute to positive outcome for children with autism

November 6, 2017
It might not surprise that good relationships create good outcomes, as meaningful relational experiences are crucial to all of us in our everyday life. However, the development of a relationship with a child with autism may ...

In autism, too many brain connections may be at root of condition

November 2, 2017
A defective gene linked to autism influences how neurons connect and communicate with each other in the brain, according to a study from Washington University School of Medicine in St. Louis. Rodents that lack the gene form ...

New autism study a "shocking wake-up call" for society, say academics

October 23, 2017
People who show characteristics of autism are more at risk of attempting suicide, according to a Coventry University study whose results are being presented to a United States federal advisory committee tomorrow.

Signaling pathway may be key to why autism is more common in boys

October 17, 2017
Researchers aiming to understand why autism spectrum disorders (ASD) are more common in boys have discovered differences in a brain signaling pathway involved in reward learning and motivation that make male mice more vulnerable ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.