A broad autism phenotype expressed in facial morphology

• Published in: Translational psychiatry Vol. 10; no. 1; p. 7
• Main Authors: Tan, Diana Weiting, Maybery, Murray T., Gilani, Syed Zulqarnain, Alvares, Gail A., Mian, Ajmal, Suter, David, Whitehouse, Andrew J. O.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 16.01.2020; Nature Publishing Group
• Subjects: 631/443; 631/477; Autistic children; Behavioral Sciences; Biological Psychology; Females; Genotype & phenotype; Masculinity; Medicine; Medicine & Public Health; Neurosciences; Pharmacotherapy; Psychiatry; Siblings
• ISSN: 2158-3188; 2158-3188
• DOI: 10.1038/s41398-020-0695-z

Autism spectrum disorder is a heritable neurodevelopmental condition diagnosed based on social and communication differences. There is strong evidence that cognitive and behavioural changes associated with clinical autism aggregate with biological relatives but in milder form, commonly referred to as the ‘broad autism phenotype’. The present study builds on our previous findings of increased facial masculinity in autistic children (Sci. Rep., 7:9348, 2017) by examining whether facial masculinity represents as a broad autism phenotype in 55 non-autistic siblings (25 girls) of autistic children. Using 3D facial photogrammetry and age-matched control groups of children without a family history of ASD, we found that facial features of male siblings were more masculine than those of male controls ( n   =  69; p   <  0.001, d  = 0.81 [0.36, 1.26]). Facial features of female siblings were also more masculine than the features of female controls ( n   =  60; p   =  0.005, d  = 0.63 [0.16, 1.10]). Overall, we demonstrated for males and females that facial masculinity in non-autistic siblings is increased compared to same-sex comparison groups. These data provide the first evidence for a broad autism phenotype expressed in a physical characteristic, which has wider implications for our understanding of the interplay between physical and cognitive development in humans.