October 20, 2011

Facial differences in autistic boys

If any readers have had the opportunity to interact with large numbers of autistic children, it would be interesting to see if these findings agree/disagree with their subjective impressions.

Autistic Facial Characteristics Identified
Aldridge and colleagues found the following distinct differences between facial characteristics of children with autism and those of typically developing children:
  • Children with autism have a broader upper face, including wider eyes.
  • Children with autism have a shorter middle region of the face, including the cheeks and nose.
  • Children with autism have a broader or wider mouth and philtrum -- the divot below the nose, above the top lip.
Molecular Autism 2011, 2:15 doi:10.1186/2040-2392-2-15

Facial phenotypes in subgroups of pre-pubertal boys with autism spectrum disorders are correlated with clinical phenotypes

Kristina Aldridge et al.

Abstract (provisional)
Background
The brain develops in concert and in coordination with the developing facial tissues, with each influencing the development of the other and sharing genetic signaling pathways. Autism spectrum disorders (ASDs) result from alterations in the embryological brain, suggesting that the development of the faces of children with ASD may result in subtle facial differences compared to typically developing children. In this study, we tested two hypotheses. First, we asked whether children with ASD display a subtle but distinct facial phenotype compared to typically developing children. Second, we sought to determine whether there are subgroups of facial phenotypes within the population of children with ASD that denote biologically discrete subgroups.

Methods
The 3dMD cranial System was used to acquire three dimensional stereophotogrammetric images for our study sample of 8- to 12-year-old boys diagnosed with essential ASD (n = 65) and typically developing boys (n = 41) following approved Institutional Review Board protocols. Three dimensional coordinates were recorded for 17 facial anthropometric landmarks using the 3dMD Patient software . Statistical comparisons of facial phenotypes were completed using Euclidean Distance Matrix Analysis and Principal Coordinates Analysis. Data representing clinical and behavioral traits were statistically compared among groups by using chi2 tests, Fisher's exact tests, Kolmogorov-Smirnov tests and Student's t-tests where appropriate.

Results
First, we found that there are significant differences in facial morphology in boys with ASD compared to typically developing boys. Second, we also found two subgroups of boys with ASD with facial morphology that differed from the majority of the boys with ASD and the typically developing boys. Furthermore, membership in each of these distinct subgroups was correlated with particular clinical and behavioral traits.

Conclusions
Boys with ASD display a facial phenotype distinct from that of typically developing boys, which may reflect alterations in the prenatal development of the brain. Subgroups of boys with ASD defined by distinct facial morphologies correlated with clinical and behavioral traits, suggesting potentially different etiologies and genetic differences compared to the larger group of boys with ASD. Further investigations into genes involved in neurodevelopment and craniofacial development of these subgroups will help to elucidate the causes and significance of these subtle facial differences.

Link

9 comments:

pconroy said...

My son has been diagnosed with ASD, and has those 3 features exactly.
My brother has undiagnosed ASD and has those 3 features exactly.

Onur said...

The brain develops in concert and in coordination with the developing facial tissues, with each influencing the development of the other and sharing genetic signaling pathways. Autism spectrum disorders (ASDs) result from alterations in the embryological brain, suggesting that the development of the faces of children with ASD may result in subtle facial differences compared to typically developing children.

Boys with ASD display a facial phenotype distinct from that of typically developing boys, which may reflect alterations in the prenatal development of the brain.


Similar to the situation in Down syndrome.

Matt said...

Broader and shorter upper face - sounds like facial masculinzation to me, although of course that's usually also connected with a relatively larger (longer) lower facial jaw region (which is why the whole male face including the jaw is similar or slightly narrower to the female face).

http://tinyurl.com/3rgf688
http://tinyurl.com/625hv5d

And there is the "male brain" theory of autism...

beltane said...

One of my sons has Aspergers and he also has these features, very different from those of his brothers.

eurologist said...

I look like that - but then again, so does everyone on my father's side of the family.

More seriously, I think it would have been great had they tested the fathers, as well. I know several families with ASD where the fathers (or other siblings) only look slightly less than this stereotype. In other words, many of the inheritable bits are likely expressed outside before becoming clinically important.

pconroy said...

@eurologiest,

My mother's 2 brothers look like this as well, and they are Asperger like, but undiagnosed ASD. In turn my maternal great-uncles also looked like this, and included an inventor, a brilliant mathematician and so on. So in my family these traits are inherited on the maternal line.

I have some Asperger like traits myself, but have a wide mid-face.

eurologist said...

To me it looks like there is a combination of genes that give people enhanced language, math, art, and music ability - but once it is too much, it is decidedly too much.

Evolution put up with this because many low-level ASD people (while somewhat annoying) are relatively easy to deal with, can be successfully integrated, usually don't cause any problems, and yet may be exceptionally productive, at important times.

As many, at times I have contemplated whether some of this is an ancient / Neanderthal trait. ASD often presents itself as high intelligence without the expected attached high social skills...

eurologist said...

BTW,

"So in my family these traits are inherited on the maternal line."

this seems unusual - I thought this was largely on the male lineage. But perhaps I am wrong, because I personally know two families in which the mother seems to have been the larger contributor (based on physiology and general interaction).

Creative said...

Might be of interest for some readers and affected.

The association between tick-borne infections, Lyme borreliosis and autism spectrum disorders

http://www.lymeinducedautism.com/images/TBILB_Autism.pdf