A new study has found that people with mutations in the top autism gene CHD8 tend to be tall and have large heads, in addition to having intellectual disability. Researchers have defined this condition as “CHD8 overgrowth syndrome.”
The study, led by medical geneticist John Graham and his team of researchers at Cedars-Sinai Medical Center in Los Angeles, focused on 27 people with CHD8 mutations. Of those 27 participants, 21 were male and 6 female, all between the ages of 1 and 27. 23 of the participants have a head circumference, height, or both in the 97th percentile or above for their age. The results of the study were published in the American Journal of Medical Genetics Part C: Seminars in Medical Genetics.
In addition to unusual head size, the researchers noted other traits in participants, such as low muscle tone, seizures, spinal curvature, umbilical hernia, flat feet, and curved pinky fingers.
Konstantinos Zarbalis, an associate professor of pathology and laboratory medicine at the University of California, said it would be “interesting maybe to find out to what extent other organs are affected, and whether an increase in height means also a general increase in organ size.”