Older fathers more likely to have autistic children

September 04, 2006

Children of men age 40 and older have a significantly increased risk of having autism spectrum disorders compared with those whose fathers are younger than 30 years, according to an article in the September issue of Archives of General Psychiatry, one of the JAMA/Archives journals.

Autism is characterized by social and language abnormalities and repetitive patterns of behavior, according to background information in the article. Autism and related conditions, known collectively as autism spectrum disorders, have become increasingly common, affecting 50 in every 10,000 children as compared with five in 10,000 two decades ago. This increase is partially due to higher levels of awareness and changes in diagnosis processes, but could also reflect an increase in incidence of autism, according to the authors. Older parental age has previously been linked to abnormalities in the brain development of children; however, few studies have effectively examined the effect of mothers' and especially fathers' ages on autism.

Abraham Reichenberg, Ph.D., of the Mount Sinai School of Medicine, New York, and Institute of Psychiatry, King's College London, and colleagues evaluated this association in children born during the 1980s in Israel. All men and three-fourths of the women born in these years were assessed by the draft board at age 17, during which time any psychiatric disorders were recorded. Dr. Reichenberg and colleagues obtained draft board information and the age of the father for 318,506 individuals; age of the mother was available for 132,271 of those.

Two hundred and eight individuals in the larger group (a rate of 6.5 per 10,000) and 110 in the group with both maternal and paternal ages (8.3 per 10,000) had a diagnosis of autism spectrum disorder, according to the information in the draft board registry. Among the paternal age groups of 15 to 29 years, 30 to 39 years, 40 to 49 years and older than 50 years, there were 34 cases, 62 cases, 13 cases and one case, respectively, of autism spectrum disorders. Advancing age among fathers was associated with increased risk of autism. This association persisted after the researchers controlled for year of birth, socioeconomic status and the mother's age, such that the odds of autism spectrum disorder were nearly six times greater among children of men age 40 and older than those of men 29 years and younger. Older age among mothers was not associated with autism after researchers factored in the effect of the father's age.

The authors discuss several possible genetic mechanisms for the paternal age effect, including spontaneous mutations in sperm-producing cells or alterations in genetic "imprinting," which affects gene expression. "It is important to keep in mind, however, that age at paternity is influenced by the sociocultural environment and varies across societies and over time," they continue. "In a given population, a change in the sociocultural environment could produce a change in paternal age at birth. In theory, it could thereby lead to a change in the incidence of genetic causes of autism."

"Although further work is necessary to confirm this interpretation, we believe that our study provides the first convincing evidence that advanced paternal age is a risk factor for autism spectrum disorder," they conclude.
-end-
(Arch Gen Psychiatry. 2006;63:1026-1032. Available pre-embargo to the media at www.jamamedia.org.)

Editor's Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

For more information, contact JAMA/Archives Media Relations at 312/464-JAMA (5262) or e-mail mediarelations@jama-archives.org.

The JAMA Network Journals

Related Autism Articles from Brightsurf:

Autism-cholesterol link
Study identifies genetic link between cholesterol alterations and autism.

National Autism Indicators Report: the connection between autism and financial hardship
A.J. Drexel Autism Institute released the 2020 National Autism Indicators Report highlighting the financial challenges facing households of children with autism spectrum disorder (ASD), including higher levels of poverty, material hardship and medical expenses.

Autism risk estimated at 3 to 5% for children whose parents have a sibling with autism
Roughly 3 to 5% of children with an aunt or uncle with autism spectrum disorder (ASD) can also be expected to have ASD, compared to about 1.5% of children in the general population, according to a study funded by the National Institutes of Health.

Adulthood with autism
The independence that comes with growing up can be scary for any teenager, but for young adults with autism spectrum disorder and their caregivers, the transition from adolescence to adulthood can seem particularly daunting.

Brain protein mutation from child with autism causes autism-like behavioral change in mice
A de novo gene mutation that encodes a brain protein in a child with autism has been placed into the brains of mice.

Autism and theory of mind
Theory of mind, or the ability to represent other people's minds as distinct from one's own, can be difficult for people with autism.

Potential biomarker for autism
A study of young children with autism spectrum disorder published in JNeurosci reveals altered brain waves compared to typically developing children during a motor control task.

Autism often associated with multiple new mutations
Most autism cases are in families with no previous history of the disorder.

State laws requiring autism coverage by private insurers led to increases in autism care
A new study led by researchers at the Johns Hopkins Bloomberg School of Public Health has found that the enactment of state laws mandating coverage of autism spectrum disorder (ASD) was followed by sizable increases in insurer-covered ASD care and associated spending.

Autism's gender patterns
Having one child with autism is a well-known risk factor for having another one with the same disorder, but whether and how a sibling's gender influences this risk has remained largely unknown.

Read More: Autism News and Autism Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.