Genetics versus Environment in Autism Spectrum Disorders

A recent study conducted by Dr. Joachim Hallmayer and colleagues has received significant media attention over their findings that environmental factors may play a larger role than genetic factors in the development of autism spectrum disorders (ASDs). When evaluating the significance of genetic versus environmental influences, it is useful to examine twins. Twins are a valuable population to study because they share similar genes. Identical twins share close to 100 percent of their genetic makeup while fraternal twins share roughly 50 percent. Furthermore, twins typically share the same environment during their early development (e.g., in utero, infancy, early childhood, etc.). For these reasons, Dr. Hallmayer and colleagues set out to perform a population-based twin study on genetic versus environmental involvement in the development of ASD.

Potential participants were identified through the California Department of Developmental Services (DDS). Both identical and fraternal twin pairs were eligible to participate if they were born between 1987 and 2004, and at least one twin was reported to have an ASD diagnosis. A total of 1,156 twin pairs were identified through the DDS, however, due to limited participation from families, only 202 twin pairs were included in the study. All participants received comprehensive diagnostic evaluations to confirm diagnoses of autistic disorder or broader ASD.

ASD concordance rates, meaning the proportion of twin pairs in which both twins had an ASD diagnosis, were measured with respect to diagnosis, gender, and twin type (you can view these rates here). Using the concordance data, Dr. Hallmayer and colleagues were able to estimate the involvement of genetics versus shared environment in the development of autistic disorder and ASD. The results indicated that genetics play roughly a 37 percent role in the development of autistic disorder, while shared environment plays about a 55 percent role. Similar findings were revealed for ASD indicating that genetics play roughly a 38 percent role while shared environment plays roughly a 58 percent role.

Dr. Hallmayer and colleagues’ findings offer preliminary evidence that environmental factors may play a greater role in the development of ASD than genetic factors. Since ASD has previously been regarded as a genetic disorder, the majority of research has been focused on identifying possible genetic causes. The results of this study suggest that, in the future, more research should focus on identifying possible environmental causes in addition to genetic causes.

If you are interested in reading the full article, you can access it here.

References

Hallmayer, J., Cleveland, S., Torres, A., Phillips, J., Cohen, B., Torigoe, T.,… Risch, N. (in press). Genetic heritability and shared environmental factors among twin pairs with autism. Archives of General Psychiatry. doi: 10.1001/archgenpsychiatry.2011.76

  • E-Mail
  • Facebook
  • Twitter
  • LinkedIn
  • Tumblr
  • Technorati
  • Reddit
  • MySpace
  • Google Buzz
  • Delicious
This entry was posted in Autism Research and tagged , , , . Bookmark the permalink. Trackbacks are closed, but you can post a comment.

13 Trackbacks

  1. By check my blog on June 25, 2012 at 2:59 pm

    Recent Blogroll Additions……

    [...]usually posts some very interesting stuff like this. If you’re new to this site[...]……

  2. By Ckeck mi out on July 2, 2012 at 6:38 am

    Websites worth visiting…

    [...]here are some links to sites that we link to because we think they are worth visiting[...]……

  3. By disaprovee on July 8, 2012 at 2:50 am

    Sites we Like……

    [...] Every once in a while we choose blogs that we read. Listed below are the latest sites that we choose [...]……

  4. By workout supplements on July 9, 2012 at 3:27 am

    Recent Blogroll Additions……

    [...]usually posts some very interesting stuff like this. If you’re new to this site see more on best pre workout supplement[...]……

  5. By Mauritius Property Rental on July 9, 2012 at 7:31 am

    Gems from the internet…

    [...]very few websites that happen to be detailed below, from our point of view are undoubtedly well worth checking out[...]……

  6. By quiet title on July 9, 2012 at 5:03 pm

    Gems form the internet…

    [...]very few websites that happen to be detailed below, from our point of view are undoubtedly well worth checking out[...]……

  7. By Appartements Ile Maurice on July 9, 2012 at 11:01 pm

    Check this out…

    [...] that is the end of this article. Here you’ll find some sites that we think you’ll appreciate, just click the links over[...]……

  8. By Location Vacances Ile Maurice on July 11, 2012 at 12:26 am

    Cool sites…

    [...]we came across a cool site that you might enjoy. Take a look if you want[...]……

  9. By kitchen on July 11, 2012 at 3:29 pm

    Websites you should visit…

    [...]below you’ll find the link to some sites that we think you should visit[...]……

  10. By compare auto insurance prices on July 11, 2012 at 5:03 pm

    … [Trackback]…

    [...] There you will find 62319 more Infos: blog.centerforautism.com/2011/07/11/genetics-versus-environment-in-autism-spectrum-disorders/ [...]…

  11. By Pattaya forum on July 12, 2012 at 9:53 am

    Blogs ou should be reading…

    [...]Here is a Great Blog You Might Find Interesting that we Encourage You[...]……

  12. By Gold Coast Australia on July 12, 2012 at 10:27 am

    Visitor recommendations…

    [...]one of our visitors recently recommended the following website[...]……

  13. By pantaloni online on July 12, 2012 at 11:51 am

    Websites you should visit…

    [...]below you’ll find the link to some sites that we think you should visit[...]……

Post a Comment

Your email is never published nor shared. Required fields are marked *

*
*

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>