Abstract
When conducting whole‐genome analysis, countless variants different from the standard human sequence are identified in each individual. Among these, rare variants with low frequency may exert a strong influence on the onset of psychiatric disorders. It is important to note that possessing variants with a strong impact on the onset of psychiatric disorders does not necessarily lead to the occurrence of the disorder. However, rare variants that may strongly influence the onset of psychiatric disorders tend to coexist with other psychiatric disorders, including intellectual disabilities, and serious physical illnesses, providing valuable information on clinical course. Moreover, elucidating pathogenesis and drug development based on variants with a strong impact on onset is promising. On the other hand, it has been suggested that polygenic risk scores calculated by common variants involved in psychiatric disorders and symptoms may provide information related to the diverse clinical symptoms of each individual. In the future, as the cost of whole‐genome sequencing, which deciphers the entire sequence of the human genome, continues to decrease, it is expected that analyses integrating rare variants and common variants will be conducted on a large‐scale sample. However, it is necessary to thoroughly consider how to obtain useful results.
