Effects of the Interaction of the ANKK1/DRD2 TaqIA and HTR2C Cys23Ser Polymorphisms on Approach Motivation in Schizophrenia Patients and Healthy People

Neuroscience and Behavioral Physiology - Objective. To assess the association of the DRD2 gene and its interaction with the HTR2C gene with the characteristics of the hedonistic and activatory...     

Association of 5-HTTLPR Serotonin Transporter Gene Polymorphism and Val66Met Brain-Derived Neurotrophic Factor Gene Polymorphism with Auditory N100 Evoked Potential Amplitude in Patients with Endogenous Psychoses

We studied the relationship between genes of serotonin transporter and brain-derived neurotrophic factor and parameters of AEP N100 wave to a non-significant stimulus in patients with endogenous mental diseases. In patients with endogenous psychoses, a significant effect of BDNF Val66Met marker on N100 wave amplitude was revealed: the mean N100 amplitude was higher in carriers of Val/Val genotype compared to Val/Met genotype carriers. The effect of the 5-HTTLPR marker on the wave amplitude was less pronounced (tendency): the SS genotype was associated with higher N100 amplitude. Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 146, No. 11, pp. 541–544, November, 2008     

The Role of Genotype-Environment Interactions in the Development of Symptoms of Anxiety and Depression in Stress Associated with Disease in a Family Member

The relationship between the 5-HTTLPR and BDNF Val66Met marker genotypes and symptoms of depression and anxiety associated with stress resulting from severe chronic illness in a family member was studied. Genotyping was performed in groups of 214 unaffected parents of patients with schizophrenia and 100 control subjects. The Met*ss diplotype was associated with increases in depressive tendencies (MMPI test) in the parents of patients but not in the control group, while among parents this was the case in the subgroup of parents whose children had the most severe symptoms. These results suggest that the interaction of polymorphic 5-HTT and BDNF genes may mediate the relationship between objective and subjective burden of disease.     

The Cys allele (the Ser311Cys polymorphism) of the dopamine d2 receptor is associated with schizophrenia and impairments to selective attention in patients

We report here our studies of the Ser311Cys polymorphism of the D2 dopamine receptor gene in 366 patients with schizophrenia and 387 control subjects. The incidence of the Cys allele was found to be greater (p < 0.009) among patients than controls (8.5% and 3.9%, respectively). Selective attention was also studied on the basis of assessment of parameters of the P300 wave of auditory evoked potentials in 66 patients with different genotypes – SerSer and SerCys (the CysCys genotype was not seen among the patients). This revealed a significant influence of genotype (p = 0.01) on the latent period (LP) of the P300 wave in the frontal, central and temporal leads. In carriers of the Cys allele, which is associated with the risk of developing schizophrenia, LP was longer than in subjects with other genotypes, which is evidence for slowing of mental processes associated with activation of attention resources in these subjects. Thus, the results obtained here support data obtained previously for other populations showing that the Cys allele is associated with schizophrenia, and we also observed an association between this allele and degradation of selective attention in patients.