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1)Department of Psychiatry, Faculty of Medicine, Juntendo University, Tokyo, Japan2)Department of Molecular Pathology of Mood Disorders, Faculty of Medicine, Juntendo University, Tokyo, Japan3)Laboratory for Molecular Pathology of Psychiatric Disorders, RIKEN Center for Brain Science, Saitama, JapanKey words: genomics, psychiatric disorder, bipolar disorder, schizophrenia, autism spectrum disorder (ASD)2Corresponding author: Masaki NishiokaDepartment of Psychiatry, Faculty of Medicine, Juntendo UniversityDepartment of Molecular Pathology of Mood Disorders, Faculty of Medicine, Juntendo UniversityHongo 2-1-1, Bunkyo-ku, Tokyo, 113-8421, JapanTEL&FAX: +81-3-5802-1070　E-mail: m.nishioka@juntendo.ac.jp354th Triannual Meeting of the Juntendo Medical Society “Recent topics in Psychiatry” 〔Held on sep. 9, 2021〕〔Received　Nov. 4, 2021〕〔Accepted　Nov. 24, 2021〕J-STAGE Advance published date: Feb. 16, 2022Copyright © 2022 The Juntendo Medical Society. This is an open access article distributed under the terms of Creative Commons Attribution License (CC BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original source is properly credited. doi: 10.14789/jmj.JMJ21-0038-R　Psychiatric disorders such as bipolar disorder and schizophrenia are highly heritable. While the genetic contribution to psychiatric disorders is quite sure, specific genetic factors contributing to particular conditions have long been a mystery. Empowered by the initial report of the Human Genome Project, the analysis of the comprehensive set of the human genome, called “genomics,” became possible. Subsequent development of large-scale genomic technologies enabled us to elucidate various disease-related genetic information, accelerating our understanding of various diseases. Genomic research on psychiatric disorders is not an exception. In this Review, I introduce significant advancements in psychiatric genomics with a special focus on our investigation of bipolar disorder. International consortiums and advocacy groups accelerate psychiatric genomics, increasing the sample size and statistical power for robust findings. The genetic architecture of schizophrenia has been elucidated in both common and rare variant studies. The genetic architecture of autism spectrum disorder (ASD) has been elucidated mainly by rare variant analysis. As to bipolar disorder, common variant analysis precedes rare variant analysis, but we are struggling to elucidate relevant rare variants. While the genomic approach has explained specific genetic factors for particular disorders, overlapping risk genes or pleiotropy has been observed more than expected. The boundary in the current nosology of psychiatric disorders is more or less challenged. To understand the genotype-phenotype relation more deeply, an attempt to understand phenotypes based on genotypes, called the “genotype first” approach, has started. I discuss this new approach for better understanding and treatment of psychiatric disorders.Juntendo Medical Journal2022. 68(1), 2-11Special ReviewsIntroduction: psychiatry and geneticsPsychiatric disorders such as bipolar disorder and schizophrenia are global medical problems afflicting many individuals with severe suffering. The societal cost of bipolar disorder and schizo-phrenia is estimated high among various medical diseases1). Bipolar disorder afflicts the patients and their families with severe depression and problem-atic behaviors from manic episodes. Schizophrenia leads to unbearable suffering through annoying hallucinations, persecutory delusions, social with-drawal, and cognitive decline. Despite the patients’ woes, we have limited choice of therapeutic strategy. The adverse effects of the medications are also problematic. Besides, the effects of psychi-atric medications are serendipitously discovered, not based on our biological understanding of the mechanisms of psychiatric disorders. We need to understand the biological mechanisms of psychi-atric disorders to find a new therapeutic strategy and overcome the suffering of the patients due to The Current Progress of Psychiatric GenomicsMasaki NISHIOKA1-3)