Broader Autism Phenotype (Parents and siblings)
Simon Baron-Cohen, Rosa Hoekstra, Mark Johnson, Carrie Allison, Mike Spencer, Rosie Holt, Lindsay Chura, Jillian Sullivan, Maaike Hoeksma, Francesca Cabedo, Leanne Swain and Edward Sucksmith
We have found that parents and siblings of children with autism or Asperger Syndrome are more likely to have excellent attention to detail, higher scores on the Autism Spectrum Quotient (AQ), and show different patterns of brain activity whilst performing attentional tests and empathy tests. We are currently looking at other measures to characterize the broader phenotype in parents and siblings, such as the Empathy Quotient (EQ) and Systemizing Quotient (SQ), and how these inter-relate.
We also carried out one of the earliest 'baby sibs' studies to predict which toddlers might go on to receive a diagnosis on the autistic spectrum, by virtue of having an older sibling with a diagnosis. This used the Checklist for Autism in Toddlers (CHAT) at 18 months of age. Video analysis of interactions among baby sibs also confirmed atypical interactional synchrony as young as 4 months of age.
The ARC is a collaborator on the Baby Sibs UK Network. Other studies from the ARC have found adult first degree relatives of people on the autistic spectrum are over-represented among systemizing occupations such as engineering, mathematics, and computer science.
Our sibling studies are now extending to the neural level using MRI and DTI, and looking at brain volume in relation to head circumference.