Polymorphisms in Genes Involved in Testosterone Metabolism in Slovak Autistic Boys

Abstract

Autism spectrum disorders (ASDs) are neurodevelopment disorders which are characterized by impairments in the following core domains: social interaction, language development, verbal/nonverbal communication, and repetitive and restricted behaviors. The androgen theory of autism proposes that autism spectrum disorders develop in part due to elevated fetal testosterone levels, which correlate with a number of autistic traits. The present study evaluates androgen and estrogen levels in saliva as well as polymorphisms in genes for androgen receptor (AR), 5-alpha reductase (SRD5A2), and estrogen receptor alpha (ESR1) in the Slovak population of prepubertal (under 10 years) and pubertal (over 10 years) children with autism spectrum disorders. The examined prepubertal patients with autism, pubertal patients with autism, and prepubertal patients with Asperger syndrome had significantly increased levels of salivary testosterone (P 0.05, P 0.01, and P 0.05, respectively) in comparison with control subjects. We found a lower number of (CAG)n repeats in the AR gene in boys with Asperger syndrome (P 0.001). Autistic boys had an increased frequency of the T allele in the SRD5A2 gene in comparison with the control group. The frequencies of T and C alleles in ESR1 gene were comparable in all assessed groups. The modulating influence of studying genotypes on the effect of testosterone could provide insight into the pathogenesis of autism spectrum disorders.