RESUMO
Schizophrenia with early onset is a relatively rear form of the disease which characterized by severe chronic course and poor outcome. In the present paper, we studied several genes possibly involved in the pathogenesis of this form. These are genes for brain-derived neurotrophic factor (Val66Met polymorphism), serotonin transporter (5-HTTLPR), serotonin receptor type 2A (T102C) and dopamine receptor D2 (Taq1A). Sixty-five patients (age at onset before 15 years) and 111 healthy controls were included in the study. Out of all genes tested, the association was found only for the Val66Met BDNF polymorphism. Frequency of the ValVal genotype was higher in the group of patients (p=0.03; OR 2.1 CI 1.1-4.0) compared to the controls. These results were consistent with our previous study which was carried out on the sample of schizophrenic patients with later age of disease onset. In this study, the frequency of the ValVal genotype was higher only in the group of patients with chronic schizophrenia compared to the controls. It is concluded that the ValVal BDNF genotype may be considered as a marker of schizophrenia with more severe course.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Esquizofrenia/genética , Adolescente , Adulto , Idade de Início , Criança , Feminino , Marcadores Genéticos , Humanos , Masculino , Polimorfismo Genético , Receptor 5-HT2A de Serotonina/genética , Receptores de Dopamina D2/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Adulto JovemRESUMO
To investigate the effect of Val66Met BDNF and 5-HTR2A T102C polymorphisms on the characteristics of voluntary and involuntary visual attention, 89 patients with schizophrenia, 91 their well relatives and 163 controls have been studied. Attention was assessed using a modified version of the Munsterberg test. The significant interaction effect of the BDNF, 5-HTR2A and diagnosis on attention characteristics was found (p=0,04). Carriers of the Val/Val genotype demonstrated higher scores of both voluntary and involuntary attention and those with the A1 (T) allele needed more time for the performance of the test. The combination of the A1 allele with a Met BDNF allele was associated with lower scores of voluntary attention and higher scores of involuntary attention. The study confirmed the impairment of selective attention in patients with schizophrenia and their relatives while any pathological changes in involuntary attention were not observed. The effect of genotypes was presented irrespective of diagnostic group studied. The data obtained suggest that carriers of the Val/Val genotype are able to allocate more attentional resources to process external stimuli. At the same time, the possibility that this polymorphism is likely associated with specific visual-spatial abilities than with attention as such or general cognitive resources can not be excluded.
Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Fator Neurotrófico Derivado do Encéfalo/genética , DNA/genética , Polimorfismo Genético , Receptor 5-HT2A de Serotonina/genética , Esquizofrenia/complicações , Adulto , Alelos , Atenção/fisiologia , Transtorno do Deficit de Atenção com Hiperatividade/sangue , Fator Neurotrófico Derivado do Encéfalo/sangue , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Receptor 5-HT2A de Serotonina/sangue , Esquizofrenia/sangue , Esquizofrenia/genética , Índice de Gravidade de DoençaRESUMO
A relationship between neurophysiological and psychological characteristics of attention was studied in 18 patients with schizophrenia and their 34 mentally healthy relatives: parents and siblings (20 subjects) and children (14 subjects). In patients, a decrease of P300 auditory evoked potentials significantly correlated with disturbances of attention stability and volume as well as characteristics of involuntary attention. At the same time, in the groups of relatives the anomalies of attention stability and attention in conditions of prolonged concentration were positively related to P300 latency.
Assuntos
Atenção/fisiologia , Potenciais Evocados Auditivos , Esquizofrenia , Psicologia do Esquizofrênico , Adulto , Criança , Interpretação Estatística de Dados , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/fisiopatologiaRESUMO
Polymorphic marker Ser9Gly of dopamine receptor D3 gene is considered perspective for associative studies of schizophrenia. Allele and genotype frequency of this polymorphism were studied in different ethnic groups of schizophrenic patients as well as the attempts have been made to reveal an association with clinical presentations of the disease. However, the results are inconsistent. The present study aimed at investigating Ser9Gly DRD3 gene polymorphism in Russian sample of schizophrenic patients. One hundred and fifty patients with ICD-10 diagnosis of schizophrenia (broad definition), 69 male and 81 female, aged 34.8+/-13.87 years, age at disease onset 24.3+/-9 years, have been examined. Control group consisted of 150 healthy subjects without family history of schizophrenia, 60 male and 90 female, aged 32.7+/-13.5 years. No between-group differences have been found for Ser9Gly DRD3 allele and genotype frequencies. However, a frequency of homozygous genotype Gly/Gly was significantly higher in female patients, comparing to female controls (p=0.038 Yate's corrected, OR 9. CI 0.95% 1.0-79.5). A role of sex-dependent association between Ser9Gly DRD3 polymorphism and schizophrenia is discussed.
