title: Association of serotonin transporter promoter gene polymorphism (5-HTTLPR) with depression in Costa Rican schizophrenic patients.
abstract: Depression and suicidal behavior are frequently observed in patients with schizophrenia. The serotonin transporter protein regulates serotonergic signaling at synapses and is encoded by a single gene (SLC6A4; Locus Link ID: 6532), located at 17q11.1-q12 with two polymorphic variants (the short and the long allele). The short allele of serotonin transporter gene has been associated with depression and suicidality in individuals who suffered negative life events and with depression in individuals with chronic psychosis.. Subjects were recruited from a genetic study of schizophrenia conducted in Costa Rica. The authors replicated their previous research, using a more narrow phenotype (only schizophrenic subjects) and a more ethnically homogenous sample (only Costa Rican schizophrenic individuals who were not included in the previous study). The authors hypothesized that subjects with at least one copy of the serotonin transporter promoter gene polymorphism (5-HTTLPR) "s" allele would have a greater history of lifetime depression and suicidability rate than those who had an "l/l" genotype. The authors analyzed 155 subjects with a DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) diagnosis of schizophrenia (73% male, age at interview 38.3, SD = 11.23). The genotype distribution was "ss" 58 (37%), "sl" 69 (45%), and "ll" 28 (18%). In the secondary analysis, the authors explored association of the "s" allele with lifetime history of suicide behavior in 173 subjects (18 more subjects than primary analysis because schizophrenic individuals were included regardless of history of depression). The authors found that subjects carrying at least one short allele had a significant increased lifetime risk for depressive syndromes (chi(2) = 5.4, df = 1, P = 0.02; odds ratio [OR] = 2.7, 95% confidence interval [CI] = 1.15-6.3). No association was found for suicidal behavior in the same sample (chi(2) = 0.928, P = 0.629). In conclusion, the genotype at the 5-HTTLPR promoter polymorphic locus increases the risk of developing major depression but not suicidal behavior during the course of the schizophrenia in these patients. Due to the small sample size, these results should be followed by definitive replication.
authors.affiliation: Psychiatric Genetics Research Center, Department of Psychiatry, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA. dr.javiercontreras@gmail.com
authors.forename: Javier
authors.initials: J
authors.lastname: Contreras
authors.forename: Sandra
authors.initials: S
authors.lastname: Hernández
authors.forename: Paulina
authors.initials: P
authors.lastname: Quezada
authors.forename: Albana
authors.initials: A
authors.lastname: Dassori
authors.forename: Consuelo
authors.initials: C
authors.lastname: Walss-Bass
authors.forename: Michael
authors.initials: M
authors.lastname: Escamilla
authors.forename: Henriette
authors.initials: H
authors.lastname: Raventos
mesh_terms: D000328:Adult; D015331:Cohort Studies; D015897:Comorbidity; D003364:Costa Rica; D003866:Depressive Disorder / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D018401:Sample Size; D012559:Schizophrenia / Q000453:epidemiology / Q000235:genetics*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D013406:Suicide, Attempted
chemical_list: D005819:Genetic Markers; D050486:Serotonin Plasma Membrane Transport Proteins