This is a blog post by Dennis Debbaudt, the father of a young man with autism and founder of Autism Risk & Safety Management (link to www.autismriskmanagement.com)
Whether living on the autism spectrum or not, we’re all part of the human condition. As humans, we all need the essentials of everyday life. We all need to work, play and love. We need work that we take pride in. We do our best and reap the rewards of doing so. We need to take a break from work and have some fun. Sports, the arts, taking a walk in the park, playing a game, reading a book. We find activities we like and get a chance to smile and relax while doing so. We need to make friends among family, neighbors, classmates, co-workers and the people we meet along the road of life. And we need to feel safe and secure while pursuing these activities.
Addressing safety and risk can be accomplished by making a plan that meets our unique needs, then making that plan a part of our daily routines.
The ultimate plan will be yours to design with people that you love and trust. The goal? That everyone can work, have fun and friends in a safe and risk free environment!
This month, Autism Speaks has updated the Autism Safety Project and released new information on safety in the home, safety in the community, and sexual abuse and other forms of mistreatment. The Autism Safety Project also includes information for first responders and other professionals who may interact with children and adults with autism. Please consider the information here as a starting point for discussion! Visit www.autismspeaks.org/safety to learn more!
Research has taught us that there’s no simple explanation for what causes autism. We know that genes play a role, but they aren’t the whole picture. Environment also matters.
However “environment” can be a tricky term, as pediatrician Perri Klass recently noted in her New York Times column. In autism research, we use the word to refer to pretty much any influence beyond inherited genes—not just exposure to pollutants or other toxic chemicals.
In fact, the environmental factors that research most strongly links to autism are influences such as maternal infection during pregnancy (especially rubella), birth complications (especially those involving oxygen deprivation), and parental age at time of conception (dad as well as mom). Parents who wait less than one year between pregnancies may be at a slightly higher risk for having a child with autism. (Conversely, there is strong evidence that mothers who take prenatal vitamins before conceiving reduce the odds that their children will develop autism.)
Clearly, countless fetuses and babies are exposed to “environmental risk factors” such as these without ever developing autism. But if a child is genetically predisposed to autism, it appears that these influences further increase the risk. For this reason, we say that environmental factors increase the risk of autism rather than cause it.
Research has suggested that many other environmental, or nongenetic, factors may increase the risk for autism. But scientists can’t yet say whether these involve direct (versus coincidental) links. Such factors include a pregnant woman’s exposure to certain chemicals such as pesticides and phthalates (commonly found in plastics) or certain drugs such as terbutaline (used to stop premature labor), valproic acid (to control seizures), and some antipsychotics and mood stabilizers. Of course, in the case of medications, any possible increased risk of autism must be balanced against a woman’s medical needs—which can likewise affect the health of her pregnancy and children.
In addition, most environmental factors associated with autism appear to increase risk only slightly and only in combination with other factors such as genetic predisposition. So it is difficult, in most cases, to pinpoint any one environmental influence. For these reasons, Autism Speaks continues to fund research on a wide range of environmental risk factors. Importantly, the more we learn about how these influences affect brain development, the better we can help the children, adults and families who are affected by autism.
Want to learn more about the research Autism Speaks is funding? On our Science Grant Search page, you can browse studies by topic and location. Finally, if you or your child is affected by autism, please consider participating in one of our clinical studies. Thanks, and please keep sending us your questions.
This post is from Guest Blogger, Stanley Nelson, M.D. Dr. Nelson is the Director for the UCLA Site of the NIH Neuroscience Microarray Consortium, and Professor of Human Genetics and Psychiatry at the David Geffen School of Medicine at UCLA. Dr. Nelson was also a co-author on last week’s collaborative Nature paper.
Investments in the genetics of autism have been substantial and the results are beginning to come forth, with last week’s announcement of the latest findings from our collaborative Autism Genome Project adding to previously identified genes and copy number variations that made last year’s Top 10 Autism Research Achievements of 2009. The latest results, funded in large part by the tremendous efforts of Autism Speaks, are interesting alone, and I hope that all have learned that there are indeed novel genes being identified that lead to autism. However, there is a perhaps more important message from the paper which relates directly to the couple hundred thousand families directly affected by an autism spectrum disorder in the US alone.
Within the recent Nature paper are compelling new findings demonstrating that autism can be caused by genetic mutations in a wide range of different genes, but the findings highlight how complex the genetic causes will be, likely in the hundreds. With this level of complexity, it is also clear that this sized sample that took 15-20 years to collect at the cost of tens of millions of dollars including molecular testing and analytical effort, we were only able to find genetic causes for a small minority of the children with autism (a few percent). So detecting the meaningful gene variants is largely a game of statistics. With the relatively small size of the autism samples available to us today, many gene mutations that may be causative in an individual with autism will go ‘undetected’ because our sample size lacks the statistical power to identify them as definitively associated with autism. This is because these causative variants are each “rare” in the whole autism population. Even though rare, each gene variant that confers risk is important. Why? When considered together, these gene variants will collectively explain the majority of cases of the disorder, as well as inform us greatly about the still largely unresolved biological causes, both genetic and environmental. To get us to the next phase of understanding the genetic risk of autism, we need a way to cost-effectively recruit tens of thousands of affected individuals and their families to enable the appropriate large scale genetic studies needed to address this pressing scientific need. My attitude is well described in an interview written by Nancy Shute at US News and World Report.
Until recently, we have not had a nationwide infrastructure that could allow anyone in the US to participate with a child with a diagnosis of autism. That has changed with the initiation of the IAN Genetics Project, funded by Autism Speaks through the High Risk, High Impact Initiative. Using the web portal of the IAN Genetics Project, families provide information about their child through simple web-based questionnaires that require only a few hours effort from home, anytime. Families also give consent for the DNA collection portion of study online. Interested families may participate in this study by taking their child to one of 1,600 blood draw sites nationwide with our corporate partner, Labcorp. This is all made possible through the Interactive Autism Network, and more information can be found at IANPROJECT.ORG, where I encourage all families with an affected child to register and complete the requested questionnaires. For those interested in learning more about the DNA Study, specific information can be found by following this link. Any questions about the project can be answered by IAN staff, who can be reached through the link.
Please register at IANPROJECT.ORG, even if not interested in the DNA Study. Simply filling out the online forms provides powerful new data to researchers that can only come from many thousands of individual families taking the time to help solve the complex issues of autism beyond genetics alone. Together we can take this next step to help reveal the causes of autism and help alleviate the struggles of those living with autism today.
These numbers may sound alarming, but lets further discuss what they mean. The 51% increase in risk for mothers over 40 can also be described as approximately 1.5 times the chances of having a child with autism compared to mothers 25-29. In other words, the increased chance of having a child with autism was less than two-fold among this group. Thus, mother’s age and father’s age only slightly increased the risk for autism, and should not be viewed as a specific cause of autism. While the exact biological mechanism behind the relationship between delayed parenthood and ASD is unknown and warrants further investigation, it is well understood that pregnancy in older individuals is associated with higher risk for low birth weight, prematurity, and chromosomal abnormalities. We also know that prematurity is a risk factor for autism spectrum disorders (ASD). It also is important to keep in mind that the majority of pregnancies in older fathers and mothers are healthy.
Do changes in the ages at which parents are having children explain the dramatic increase in prevalence of ASD? The study examined births over a decade, a period during which the prevalence of ASD has increased by over 600%. The authors estimated that advanced maternal age only accounts for 4.6% of the increase in autism cases in California during the study period. Thus, it is clear that, while changes in the age at which parents are having children may account for some of the increase in prevalence of autism, a large amount of the increase in prevalence remains unexplained.
As with any study, there are many methodological details to be considered. The strength of this study lies in the large population considered. These findings reinforce other data reporting parental age is a risk factor for autism. The study population came from the California Department of Developmental Services (DDS), which is estimated to capture about 75-80% of all “true” autism cases. To be included in the DDS, parents had to actively seek out services. As such, parents of autism cases in the DDS are likely to have higher levels of education and socioeconomic status, and are perhaps older than what would be found in a population-based sample. We know from this and other research that higher levels of education and sociecomic status are associated with higher rates autism (perhaps because people in this demographic category are more likely to seek diagnostic services), so it is possible that this study may overestimate the effect of parental age on autism risk. Also, it is worth noting that this study considered cases of autistic disorder only, not diagnoses from the rest of the autism spectrum.
To summarize, it is important to remember that as we dig deeper into different contributions to autism risk, we will uncover different pieces of the larger puzzle that may not seem to fit, at least at first. Some, pieces, like this one regarding parental age, are especially intriguing because they blend biological with the socio-environmental factor of delayed parenthood. As for biology, it is also true that as people age, modifications occur in the way the genetic code is read. This field of research known as epigenetics and is one part of the larger study of gene x environment interactions. The topic of gene-environment interaction has been reaching our community with increasing frequency and so Autism Speaks staff and some Guest Scientists will be offering a series of blog posts specifically on these topics. Please stay tuned. We look forward to putting this puzzle together with you.
To learn more about the recent findings in autism epidemiology, including additional findings on the effects of parental age, please see our list of the Top Ten Science Accomplishments of 2009.
Reference: Shelton JF, Tancredi DJ and Hertz-Picciotto I (2010) Independent and Dependent Contributions of Advanced Maternal and Paternal Ages to Autism Risk. Autism Research. 3: 1-10.