Genetics of autism spectrum disorders

Autism is a group of etiology and clinical heterogeneous neurodevelopmental disorders with an onset before 3 years old. It has 3 core characteristics: deficits in verbal communication; impairment of social interaction; restricted interests and repetitive behaviors. The incidence is increasing over time worldwide. Twin and family studies have demonstrated that autism has a high heritability (>90%). Although certain progress of autism genetic study has been made in the last decades and several autism susceptibility genes and loci have been identified, there are still about 70%-80% of patients for whom an autism-related genetic change cannot be identified.