Genetic evaluation of children with autism spectrum disorders in developing and low-resource areas

Abstract

Autism spectrum disorder is a neurodevelopmental disorder in which genetic factors play key roles. Limited research has been conducted on genetic testing of children with autism spectrum disorder in low middle-income countries. This prospective cross-sectional study was conducted at the pediatric neurology clinics of three university hospitals in Jordan. Data were obtained from a convenience sample of parents of children with autism spectrum disorder who received care at these hospitals. Research personnel interviewed the parents and completed a questionnaire. A total of 274 parents were interviewed. A minority of children received chromosomal microarray (14.6%) or fragile X syndrome (4.4%) testing, as recommended by clinical guidelines. Karyotyping was performed in 103 (37.6%) patients, and whole-exome sequencing was performed in 9 (3.3%). The most common reason for not performing the recommended diagnostic investigations was that they were not ordered by the physician (185; 67.5%). The majority of children underwent non-genetic evaluations, including brain magnetic resonance imaging (222; 81.0%), electroencephalogram (221; 80.7%), and brain computed tomography scans (136; 49.6%). Only a minority of children with autism spectrum disorder in Jordan receive genetic workup, which may reflect a gap in physicians’ knowledge of clinical guidelines, as well as the availability and affordability of these tests. Lay abstract Autism is the most common neurodevelopmental disorder in children worldwide. Genetic factors play an important role in the risk of developing autism. Determining the genetic cause of autism is key to understanding the biological processes that lead to the clinical manifestations of autism, and can inform the management and even prevention of this condition. Establishing genetic causes of autism requires collection of genetic data on a global scale. Limited research on genetic testing for individuals with autism is available from developing countries in low-resource regions. In this study, we explored the types of investigations ordered for Jordanian children with autism by their physicians. A representative sample of parents of children with autism in Jordan was questioned about the studies that their children received. We found that the recommended genetic testing was only performed in a small number of children with autism. In contrast, most children in the sample received non-genetic testing, which is not routinely recommended. We also explored the sociocultural factors that may influence the decision to perform genetic testing in this population. We discuss our findings in light of the data available from other developing and developed countries.