While, in general, a certain number of clinical psychiatrists might not be familiar with molecular biology, the mechanisms of mental illnesses have been uncovered by molecular biology for decades.
 Among mental illnesses, even biological psychiatrists and neuroscientists have paid less attention to the biological treatment of autism spectrum disorder (ASD) than Alzheimer's disease and schizophrenia since ASD has been regarded as a developmental disorder that was seemingly untreatable. However, multifaceted methods of molecular biology have revealed the mechanisms that would lead to the medication of ASD.
 In this article, how molecular biology dissects the pathobiology of ASD is described in order to announce the possibilities of biological treatment for clinical psychiatrists.
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