Does the genetic expression of specific physical traits ever correlate to behaviour?
Aldridge et al. (2011) show a correlation between facial phenotypes and autism spectrum disorders (ASD) in a sample of 8-12 year old boys.

They studied two groups of boys, 65 that had been diagnosed with ASD and 41 who had not. They collected 3D images of the faces and looked for similar patterns among the two groups. They found a significant association between some phenotypes and ASD. But, as with most studies, the results are complex; there a distinct sub-groups within the ASD group.

Keep in mind that this is an association study -- no causation is shown.