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Takaki Tanifuji,1 Satoshi Okazaki,1 Ikuo Otsuka,1 Tadasu Horai,1 Yutaka Shinko,1 Saehyeon Kim,1 Ichiro Sora,1 Akitoyo Hishimoto1,2 1Department of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan; 2Department of Psychiatry, Yokohama City University Graduate School of Medicine, Yokohama, JapanCorrespondence: Akitoyo HishimotoDepartment of Psychiatry, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa, Yokohama, 236-0004, JapanTel +81-45-787-2667Fax +81-45-783-2540Email hishipon@yokohama-cu.ac.jpBackground: Monoamine oxidase-A (MAO-A) decomposes dopamine and serotonin, and decreased MAO-A expression increases monoamine levels and is related to the pathophysiology of schizophrenia. Previous studies have reported that variable number of tandem repeats (VNTR), namely, upstream (u)VNTR, and some single nucleotide polymorphisms (SNPs) in the MAOA gene are associated with schizophrenia.Methods: We investigated the two VNTRs and their related SNPs (rs6323 and rs1137070) in the MAOA gene promoter in 859 patients with schizophrenia and 826 healthy controls. Distal (d)VNTR and uVNTR were genotyped with fluorescence-based fragment polymerase chain reaction assays, and rs6323 and rs1137070 with TaqMan SNP genotyping assays.Results: Neither the genotype nor allelic frequency of the VNTRs or SNPs showed significant differences between the schizophrenia and control groups. On the other hand, analysis of the dVNTR-uVNTR-rs6323-rs1137070 haplotype showed significant association for nine repeats (9R)-3R-T-C in female patients (corrected p = 0.0006, odds ratio [confidence interval] = 2.17 [1.446– 3.257]).Conclusion: Our findings provide novel evidence that MAOA gene polymorphisms are associated with an increased risk of developing schizophrenia in females.Keywords: haplotype, monoamine oxidase A, polymorphism, schizophrenia, variable number of tandem repeats

Hirofumi Igeta,1 Yuichiro Watanabe,1 Ryo Morikawa,1 Masashi Ikeda,2 Ikuo Otsuka,3 Satoshi Hoya,1 Masataka Koizumi,1 Jun Egawa,1 Akitoyo Hishimoto,3 Nakao Iwata,2 Toshiyuki Someya11Department of Psychiatry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan; 2Department of Psychiatry, Fujita Health University School of Medicine, Toyoake, Aichi, Japan; 3Department of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Hyogo, JapanCorrespondence: Yuichiro WatanabeDepartment of Psychiatry, Niigata University Graduate School of Medical and Dental Sciences, 757 Asahimachidori-ichibancho, Chuo-ku, Niigata 951-8510, JapanTel +81 25 227 2213Fax +81 25 227 0777Email yuichiro@med.niigata-u.ac.jpPurpose: Whole-exome sequencing (WES) of multiplex families is a promising strategy for identifying causative variations for common diseases. To identify rare recessive risk variations for schizophrenia, we performed a WES study in a consanguineous family with affected siblings. We then performed follow-up sequencing of SPATA7 in schizophrenia-affected families. In addition, we performed a case-control study to investigate association between SPATA7 variations and schizophrenia.Patients and methods: WES was performed on two affected siblings and their unaffected parents, who were second cousins, of a multiplex schizophrenia family. Subsequently, we sequenced the coding region of SPATA7, a potential risk gene identified by the WES analysis, in 142 affected offspring from 137 families for whom parental DNA samples were available. We further tested rare recessive SPATA7 variations, identified by WES and sequencing, for associations with schizophrenia in 2,756 patients and 2,646 controls.Results: Our WES analysis identified rare compound heterozygous missense SPATA7 variations, p.Asp134Gly and p.Ile332Thr, in both affected siblings. Sequencing SPATA7 coding regions from 137 families identified no rare recessive variations in affected offspring. In the case-control study, we did not detect the rare compound heterozygous SPATA7 missense variations in patients or controls.Conclusion: Our data does not support the role of the rare compound heterozygous SPATA7 missense variations p.Asp134Gly and p.Ile332Thr in conferring a substantial risk of schizophrenia.Keywords: Japanese, multiplex schizophrenia family, next-generation sequencing, recessive variations

Takashi Hirata, Akitoyo Hishimoto, Ikuo Otsuka, Satoshi Okazaki, Shuken Boku, Atsushi Kimura, Tadasu Horai, Ichiro Sora Department of Psychiatry, Kobe University Graduate School of Medicine, Kusunoki-cho, Chuo-ku, Kobe, Japan Background: Life expectancy is 10–20 years lower in patients with schizophrenia than in the general population. In addition, men with schizophrenia have an earlier age at onset, more pronounced deficit symptoms, poorer course, and poorer response to antipsychotic medications than women. Recent studies have indicated that loss of chromosome Y (LOY) in peripheral blood is associated with an increased risk of all-cause mortality. In order to elucidate the pathophysiology of male-specific features, we investigated the association between LOY and schizophrenia. Materials and methods: The present study included 360 Japanese men (146 patients with schizophrenia vs 214 controls). The relative amount of Y chromosome was defined as the ratio of chromosome Y to chromosome X (Y/X ratio) based on the fluorescent signal of co-amplified short sequences from the Y-X homologous amelogenin genes (AMELY and AMELX). Results: There was no significant difference in the frequency of LOY between the schizophrenia and control groups. However, longer duration of illness was associated with LOY after controlling for age and smoking status in the schizophrenia group (P=0.007, OR =1.11 [95% CI =1.03–1.19]). Conclusion: According to our results, schizophrenia may not have a remarkable effect on blood LOY; however, LOY may be associated with disease course in patients with schizophrenia. Keywords: loss of chromosome Y, schizophrenia, disease duration

Tadasu Horai,1 Akitoyo Hishimoto,1 Ikuo Otsuka,1 Tatsuhiro So,2 Kentaro Mouri,1 Naofumi Shimmyo,1 Shuken Boku,1 Noriaki Okishio,3 Ichiro Sora1 1Department of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan; 2So Mental Clinic, Kobe, Japan; 3Hyogo Mental Health Center, Kobe, Japan Background: Alcohol dependence induces low bone mineral density (BMD), predicting osteoporosis, while low and moderate alcohol consumption may even increase BMD. In recent years, undercarboxylated osteocalcin (ucOC) and tartrate-resistant acid phosphatase-5b (TRACP-5b), bone turnover markers, have gained special interest as useful indicators of low BMD. However, it remains unclear whether other alcohol-related variables (eg, duration of abstinence and continuous drinking) are linked to aberrant BMD. In addition, no previous study has investigated whether ucOC or TRACP-5b is clinically useful to predict low BMD not only in the general population, but also in alcohol-dependent subjects.Patients and methods: We recruited 275 male alcohol-dependent subjects and collected information about their drinking habits, comorbid diseases, smoking history and walking exercise behavior. BMD in each subject was determined by ultrasonography. Serum liver enzymes (AST, ALT, ALP, ChE, γ-GTP and LDH), ucOC and TRACP-5b were measured in all subjects. T-scores were calculated according to BMD for all subjects.Results: The mean T-scores of our subjects were negatively shifted compared to the general population (-0.75±1.36 SD). We divided our subjects into a normal BMD group (n=137) and a low BMD group (n=138) according to their T-scores (T-score ≥-1 SD, normal BMD; T-score

Naofumi Shimmyo,1 Akitoyo Hishimoto,1 Ikuo Otsuka,1 Satoshi Okazaki,1 Shuken Boku,1 Kentaro Mouri,1 Tadasu Horai,1 Motonori Takahashi,2 Yasuhiro Ueno,2 Osamu Shirakawa,3 Ichiro Sora1 1Department of Psychiatry, 2Division of Legal Medicine, Department of Community Medicine and Social Health Science, Kobe University Graduate School of Medicine, Kobe, 3Department of Neuropsychiatry, Kindai University Faculty of Medicine, Osaka, Japan Background: Numerous studies suggest that inflammation plays a key role in suicidal behavior. Macrophage migration inhibitory factor (MIF), a proinflammatory cytokine, has received increasing attention in depression research. However, no study has investigated whether MIF has genetic involvement in completed suicide. In this study, we sought to explore the relationship between two functional polymorphisms on the MIF gene promoter (MIF-794CATT5–8 microsatellite and MIF-173G/C single-nucleotide polymorphism [SNP]) and completed suicide by using one of the largest samples of suicide completers ever reported.Methods: The subjects comprised 602 suicide completers and 728 healthy controls. We genotyped MIF-794CATT5–8 microsatellite by polymerase chain reaction–based size discrimination assay and MIF-173G/C SNP by TaqMan® SNP genotyping assay. The allele-, genotype-, or haplotype-based association analyses between the suicide completers and the controls were carried out with the χ2 test, the Cochran–Armitage trend test, or Fisher’s exact test.Results: Analyses of allele or genotype frequency distributions of the polymorphisms studied here did not reveal any significant differences between the suicide completers and the controls. Haplotype analysis also revealed no association with completed suicide.Conclusion: To our knowledge, this is the first study that has examined the genetic association between MIF and completed suicide. Our results suggest that the effects of MIF-794CATT5–8 microsatellite and MIF-173G/C SNP on the MIF gene promoter might not contribute to the genetic risk of completed suicide in the Japanese population. Keywords: MIF, suicide, microsatellite, SNP, haplotype, promoter region

Ikuo Otsuka,1 Yuichiro Watanabe,2 Akitoyo Hishimoto,1 Shuken Boku,1 Kentaro Mouri,1 Kyoichi Shiroiwa,1 Satoshi Okazaki,1 Ayako Nunokawa,2 Osamu Shirakawa,3 Toshiyuki Someya,2 Ichiro Sora1 1Department of Psychiatry, Graduate School of Medicine, Kobe University, Kobe, 2Department of Psychiatry, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, 3Department of Neuropsychiatry, School of Medicine, Kinki University, Osaka, Japan Background: Cadherin13 (CDH13) is a glycosylphosphatidylinositol-anchored cell adhesion molecule that plays a crucial role in morphogenesis and the maintenance of neuronal circuitry. CDH13 has been implicated in the susceptibility to a variety of psychiatric diseases. A recent genome-wide association study using Danish samples showed, for the first time, the involvement of a single nucleotide polymorphism (SNP) of CDH13 (intronic SNP rs8057927) in schizophrenia. Here, we investigated the association between other SNPs of CDH13 and schizophrenia and tried to replicate the association for the SNP of rs8057927, in the Japanese population.Methods: Using TaqMan® SNP genotyping assays, five tag SNPs (rs12925602, rs7193788, rs736719, rs6565051, and rs7204454) in the promoter region of CDH13 were examined for their association with schizophrenia in two independent samples. The first sample comprised 665 patients and 760 controls, and the second sample comprised 677 patients and 667 controls. One tag SNP for rs8057927 was also examined for the association with schizophrenia in the first sample set.Results: A GACAG haplotype of the five SNPs in the promoter region of CDH13 was significantly associated with schizophrenia in the first sample set (P=0.016 and corrected P=0.098). A combined analysis of the GACAG haplotype with the second sample set enhanced the significance (P=0.0026 and corrected P=0.021). We found no association between rs8057927 and schizophrenia in the first sample set.Conclusion: Our results suggest that CDH13 may contribute to the genetic risk of schizophrenia. Further replication on the association of CDH13 with schizophrenia and functional studies are required to confirm the current findings. Keywords: CDH13, promoter region, haplotype, SNP