|BioAutism speakers and organisers. Photo by Dee McGrath (QBI).|
A couple of weeks ago, I attended the BioAutism 2012 conference at the (very swanky) Queensland Brain Institute in Brisbane. It was a pretty long day for me but, although I was cursing when my alarm went off at 4:30am, it was well worth the trip.
What struck me as I sat waiting for the plane home, digesting the meeting (and a slightly plasticky pizza), is that there are a whole lot of Australian autism researchers doing a whole lot of really interesting work. If there was a theme to the meeting, it was one of people looking at familiar problems in unfamiliar and innovative ways.
Rather than trying to describe all 13 presentations, I thought I'd share three that really illustrate this point.
Broader Autism Phenotype in extended families
The first example came from a presentation by Natasha Brown, looking at the broader autism phenotype - the idea that relatives of people with autism tend to have some traits characteristic of autism, even if they don't actually meet criteria for autism themselves.
The conventional approach is to just look at a group of people who have an autistic relative and compare them to a group of people who don't. However, as Brown pointed out, it's becoming increasingly apparent that there are a wide range of different genetic events that are implicated in causing autism, so lumping relatives of different autistic people together risks losing or diluting a lot of useful information at both the clinical and the genetic level.
The approach that Brown and colleagues are taking is to identify extended families that include multiple autistic individuals, look at how different autistic traits cluster together, and then look for genetic anomalies that predict whether a person within the family will be autistic or show substantial autistic traits. Brown presented data from one family that included nine individuals with autism and 15 with the broader autism phenotype. By looking at the family tree and comparing this to the results of genetic testing, they were able to tentatively link the presence of autism or autistic traits to a small region on chromosome 17.
Gut malfunction in a mouse model of autism
A second example of a slightly leftfield approach was work presented by Elisa Hill, also of Melbourne Uni. Like other research groups across the world, she and her colleagues have been looking at the behaviour of mice with a mutation of the Neuroligin gene and the effects of different drugs on those behaviours.
But they have also been looking at how the genetic mutations affect the intestines of these mice. It turns out that we (as in us vertebrates) have a complete nervous system in our intestines, known as the enteric nervous system; and that genes expressed in the brain are also expressed in the gut. Hill and colleagues dissected out the colons of some of the mice and measured the colonic muscle contractions in response to different drug solutions. The muscle contractions were reduced in the mutant mice, suggesting that the mutation affected the way the gut works.
This is pretty interesting because many people with autism have gastro-intestinal problems, leading to the hypothesis that gut problems somehow cause autism. Hill's preliminary findings point towards an alternative explanation for this link - certain mutations that cause autism might also lead to malfunction of the gut.
Individual differences in responsiveness to intervention
Finally, Giacomo Vivanti from Latrobe University presented some preliminary findings from a study looking at the effectiveness of the Early Start Denver Model intervention. Compared to other interventions, this has a relatively good evidence base, with a randomized control trial suggesting that kids with autism on the program tend to do better than those who don't get the intervention.
However, as Vivanti noted, not all kids derive the same benefit. Some show huge improvements, but others are less responsive. So rather than just seeing whether the intervention overall had a net positive effect, the Latrobe researchers are trying to work out whether there are characteristics of individual children that predict the extent to which they are likely to benefit.
The preliminary results were encouraging and somewhat surprising. The best predictor wasn't a measure of language use or social interaction, as I would have expected, but how much the kids interacted appropriately with objects.
On reflection, this perhaps makes sense, if we assume that kids who don't interact with objects are less likely to engage in the activities that are involved in the intervention, and so are less likely to benefit. It's still very early days with this research, but I'm convinced that this strategy is the way to go for intervention research.