title: Association of polymorphism in the promoter of the melatonin receptor 1A gene with schizophrenia and with insomnia symptoms in schizophrenia patients.
abstract: Schizophrenia patients commonly have sleep disturbances. In this study, we investigated whether single nucleotide polymorphisms (SNPs) in the promoter region of the melatonin receptor genes (MTNR1A and MTNR1B) were associated with schizophrenia and with sleep problems such as insomnia and hypersomnia in schizophrenia patients. We genotyped two promoter SNPs [rs2119882 (-184T/C) of MTNR1A and rs4753426 (-1193C/T) of MTNR1B] using direct sequencing in 289 schizophrenia patients and 505 control subjects. We found that rs2119882 of MTNR1A was associated with schizophrenia in recessive model [CC vs. TT/TC, p = 0.013, odds ratio (OR) = 1.69, 95% confidence interval (CI) = 1.12-2.55]. Interestingly, in an analysis of clinical phenotypes, we found that rs2119882 of MTNR1A was also associated with insomnia symptoms of schizophrenia (recessive model, p = 0.010, OR = 2.24, 95% CI = 1.21-4.14), but not with hypersomnia symptoms as determined using the Operational Criteria checklist. However, rs4753426 of MTNR1B was not associated with either schizophrenia or clinical phenotypes. Our results suggest that MTNR1A may be a susceptibility gene for schizophrenia and may be associated with insomnia symptoms exhibited in schizophrenia patients.
authors.affiliation: Kohwang Medical Research Institute, School of Medicine, Kyung Hee University, Seoul, 130-701, Republic of Korea.
authors.forename: Hae Jeong
authors.initials: HJ
authors.lastname: Park
authors.forename: Jin Kyung
authors.initials: JK
authors.lastname: Park
authors.forename: Su Kang
authors.initials: SK
authors.lastname: Kim
authors.forename: Ah-Rang
authors.initials: AR
authors.lastname: Cho
authors.forename: Jong Woo
authors.initials: JW
authors.lastname: Kim
authors.forename: Sung-Vin
authors.initials: SV
authors.lastname: Yim
authors.forename: Joo-Ho
authors.initials: JH
authors.lastname: Chung
mesh_terms: D000328:Adult; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic / Q000235:genetics*; D044122:Receptor, Melatonin, MT1 / Q000235:genetics*; D044123:Receptor, Melatonin, MT2 / Q000235:genetics; D056910:Republic of Korea; D012559:Schizophrenia / Q000150:complications / Q000235:genetics*; D007319:Sleep Initiation and Maintenance Disorders / Q000209:etiology / Q000235:genetics*
chemical_list: D044122:Receptor, Melatonin, MT1; D044123:Receptor, Melatonin, MT2