Brief ReportsWhole-exome sequencing in a family with a monozygotic twin pair concordant for schizophrenia and a follow-up case-control study of identified de-novo variantsHoya, Satoshia; Watanabe, Yuichiroa; Nunokawa, Ayakoa,,b; Otsuka, Ikuoc; Shibuya, Masakoa,,b; Igeta, Hirofumia,,d; Hishimoto, Akitoyoe; Someya, ToshiyukiaAuthor Information aDepartment of Psychiatry, Niigata University Graduate School of Medical and Dental Sciences bMinamihama Hospital, Niigata cDepartment of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Hyogo dMano Mizuho Hospital, Sado, Niigata eDepartment of Psychiatry, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa, Japan Received 10 October 2019 Accepted 15 January 2020 Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's website, www.psychgenetics.com. Correspondence to Yuichiro Watanabe, MD, PhD, Department of Psychiatry, Niigata University Graduate School of Medical and Dental Sciences, 757 Asahimachidori-ichibancho, Chuo-ku, Niigata 951-8510, Japan, Tel: +81 25 227 2213; fax: +81 25 227 0777; e-mail: firstname.lastname@example.org Psychiatric Genetics: April 2020 - Volume 30 - Issue 2 - p 60-63 doi: 10.1097/YPG.0000000000000250 Buy SDC Metrics Abstract Whole-exome sequencing (WES) studies have shown that de-novo variants contribute to the genetic etiology of schizophrenia. WES studies of families with a monozygotic twin pair concordant or discordant for a disease may be fruitful for identifying de-novo pathogenic variants. Here, we performed WES in six individuals from one family (affected monozygotic twins, their unaffected parents, and two siblings) and identified three de-novo missense variants (CPT2 Ala283Thr, CPSF3 Val584Ile, and RNF148 Val210Ile) in the monozygotic twin pair concordant for schizophrenia. These three missense variants were not found in 1760 patients with schizophrenia or schizoaffective disorder or 1508 healthy controls. Our data do not support the role of the three missense variants in conferring risk for schizophrenia. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.