Growing Families conferences in London and Dublin, March 2020
Page URL: https://www.bionews.org.uk/page_93534

Genetic mutations in older fathers' sperm linked to autism

16 April 2012
Appeared in BioNews 652

Genetic mutations that occur spontaneously in sperm and egg cells may increase a child's risk of autism, say scientists.

These 'point mutations' are more likely to occur in sperm as men age, and the research, published in the journal Nature, fits in with previous work showing that older men are more likely to father children with the disorder. Everyone has point mutations in their DNA and most are harmless, but where they occur in important genes they can cause problems.

'These results confirm that it's not the size of the genetic anomaly that confers risk, but its location – specifically in biochemical pathways involved in brain development and neural connections', said Dr Thomas Insel, director of the National Institute of Mental Health in the US, which funded the work.

Despite the research highlighting the importance of non-inherited genes, three of the four mutations discussed in the paper were identified after gene sequencing of 549 families where both parents and the child tested were autistic. The mutations may increase a carrier's risk of developing autism by five to 20 times.

The study is published alongside two other studies investigating the role of point mutations in autism. Professor Joseph Buxbaum from the Mount Sinai School of Medicine in New York, and co-author of one of the studies, told Reuters that the three studies combined suggested that in total between 600 and 1,200 genes may contribute to the likelihood of whether people develop the condition.

One of the three studies, led by Dr Evan Eichler at the University of Washington in Seattle in the US, showed that the point mutations were four times more likely to occur in sperm cells rather than in egg cells. Dr Eichler told Reuters that the frequency of these genetic glitches developing is 'primarily driven by dad's age. That makes sense. As you get older, there are more and more chances for problems'.

The UK's National Autistic Society describes autism as 'a developmental disability affecting how a person communicates with, and relates to, other people and the world around them'. It encompasses a spectrum of disorders and people with autism range from those with a severe inability to communicate to those with Asperger's syndrome, a milder form.

Autism is a complex condition and the factors that may cause it have yet to be understood. 'Prior to the advent of new DNA sequencing technology, we were largely wandering in the dark searching for autism genes', said Professor Matthew State, of Yale School of Medicine and a co-author of one the Nature papers. 'Now we are getting a clear view of the genetic landscape and finally have the tools in hand to find a large proportion of the many genes contributing to autism'.

RELATED ARTICLES FROM THE BIONEWS ARCHIVE
25 March 2013 - by Matthew Thomas 
Men who father children later in life are more likely to have grandchildren with autism, according to research...
21 January 2013 - by Dr Victoria Burchell 
Rare genetic variants may have a significant impact on a person's risk of developing autism, research suggests...
17 September 2012 - by Dr Victoria Burchell 
A genetic test capable of predicting a person's risk of Autism Spectrum Disorders (ASDs), with an accuracy greater than 70 percent, has been developed by researchers...
10 September 2012 - by Suzanne Elvidge 
A rare form of autism, caused by a mutation that alters amino acid metabolism, could potentially be treated with a nutritional supplement, according to an international team of researchers...
28 August 2012 - by Helen Brooks 
Children of older fathers inherit more genetic mutations than those of younger fathers, according to Icelandic scientists....
26 March 2012 - by Dr Rosie Gilchrist 
Faulty genetic mechanisms particularly active in early life may lead to people developing autism, research suggests...
13 June 2011 - by Dr Lux Fatimathas 
American researchers have linked hundreds of spontaneous genetic mutations to the group of psychological syndromes called autism spectrum disorders (ASDs)...
31 May 2011 - by Mehmet Fidanboylu 
Gene activity in two brain regions is different in autism, scientists say. A US study found activity patterns were similar in the frontal and temporal lobes of people with autism, despite the lobes having different functions...
3 May 2011 - by Ata Anane 
Autism spectrum disorders are rarely out of the headlines. Take, for example, reports of last year's 'breakthrough' in the diagnosis of autism and the infamous research of Andrew Wakefield. This resource pack brings this public and medical debate into the classroom and makes it suitable for students over 16 years of age...
HAVE YOUR SAY
Log in to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions


Syndicate this story - click here to enquire about using this story.