Résumé
Objective: To investigate the correlation between the polymorphisms of locus in the promoter region of glutamate decarboxylase 1 (GAD1) gene and γ-aminobutyric acid (GABA)A receptor β-3 gene (GABRB3) and schizophrenia (SZ) in Chinese Han population. Methods: SNaPshot genotyping technique was used to detect the polymorphisms of rs3791878 and rs3749034 in the promoter region of GAD1 and rs4906902 in the promoter region of GABRB3 in 545 SZ patients (case group) and 624 healthy controls (control group). The distribution of alleles and genotypes under different genetic models between the case group and the control group in all samples were compared by SNPstats online software. The above analysis was also performed after the subjects were stratified according to gender. The correlation of G/T risk genotype of rs3791878 with the age of the first onset of male SZ was investigated by survival analysis. Results: Under over-dominant genetic model, the distribution of G/T risk genotype of rs3791878 showed statistically difference between the male SZ cases and male controls (P=0.000), and the difference was still statistically significant after Bonferroni correction (P=0.000). However, there was no significant difference in the distribution of alleles and genotypes under different genetic models of rs3749034 and rs4906902 between the case group and the control group in all samples (P>0.05), and there was also no significant difference in the distribution of alleles between the case group and the control group after them being stratified according to gender (P>0.05). Kaplan-Meier analysis showed that there was no significant difference between the age of onset of male SZ who carried G/T genotype in rs3791878 locus and that of male SZ who did not carry it (P=0.603). Conclusion: The polymorphism of rs3791878 in the promoter region of GAD1 is significantly associated with the incidence of male SZ in Chinese Han population.
Résumé
Objective • To explore the differences of event-related potential components (N400 and P600) in response to language processing between schizophrenia (SZ) patients with formal thought disorder (FTD), SZ patients without FTD, genetic high-risk subjects and healthy controls (HC). Methods • Thirty SZ patients with FTD (SZ-FTD group) and 29 SZ patients without FTD (SZ-nFTD group), who were hospitalized in Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, 22 subjects at genetic high risk who were first degree relatives of SZ patients, and 31 healthy controls (HC) were recruited. Four different types of sentences (syntactically and semantically correct, syntactically correct but semantically incorrect, syntactically incorrect but semantically correct, and syntactically and semantically incorrect) were presented to the four groups respectively with electroencephalogram recording. Repeated measurement analysis of variance was used to compare the response accuracy of the four groups and to analyze the differences in the amplitude and latency of N400 and P600 components in response to each kind of sentence among the four groups. Results • SZFTD group showed a lower accuracy rate compared with the HC group (P=0.000). Compared with the HC group, N400 amplitude in SZ-FTD group was lower in statistically significance (P=0.003), while SZ-FTD group did not show a prominent N400 component. P600 component was well evoked in four groups, and there was an interaction between semantics, syntax and group (P=0.022). By further analysis, neither SZ-FTD nor SZ-nFTD group showed significant differences in P600 amplitudes evoked by syntactically correct and syntactically incorrect sentences. There was no significant difference in P600 amplitudes evoked by semantically correct and incorrect sentences in SZ-FTD group, whereas P600 amplitudes evoked by semantically correct sentences were greater than those evoked by semantically incorrect ones in the other three groups. Conclusion • Neural activity is impaired during semantic processing in SZ. In particular, SZ-FTD patients have impairments in both semantic and syntactic processing.