Reduced visuospatial performance in children with the D2 dopamine receptor A1 allele

Abstract

Previous studies suggest a reduced dopaminergic function in subjects with the A1 (minor) allele of the D2 dopamine receptor (DRD2) gene. To explore influences on visuospatial ability as a function of the DRD2 gene, 182 alcohol- and other drug-naive sons (age 10-14) of active alcoholic, recovered alcoholic, and nonalcoholic fathers were administered a visuospatial task (Benton's Judgment of Line Orientation Test) which makes minimal motoric/verbal demands. Visuospatial scores were lower for boys with the A1 allele and for sons of active alcoholics. A1-allele boys made more errors than A2 boys on all 11 of the template lines, with the effect being largest for the rightmost presentations. In contrast, the effect of family history for alcoholism was strongest on both right and left midquadrant presentations. Moreover, separate analyses of the two types of errors produced allele but not family history of alcoholism effects when the two lines were misjudged as farther apart than they actually were and family history but not allele effects where the two lines were misjudged as closer together. These results suggest that polymorphism of the DRD2 gene and family history of alcoholism are dissociable determinants of visuospatial ability and that visuospatial defects previously observed in alcoholics may, in part, be antecedent to their drinking behavior.

Prefrontal cortical volume reduction associated with frontal cortex function deficit in 6-week abstinent crack-cocaine dependent men

“…These structural and functional abnormalities are actually premorbid and comorbid, in that they are also associated with the presence of comorbid mood and externalizing disorder symptoms and traits (e.g. Berman and Noble, 1995;Hesselbrock et al, 1991;Pihl and Peterson, 1991;Poon et al, 2000). Moreover, the comorbidity of psychiatric disorders and substance use is substantial.…”

D2 receptors binding potential is not affected by Taq1 polymorphism at the D2 receptor gene

“…The sample included 60 males and 10 females. Ethnic distribution of the sample was: 50 European Americans (EA), 16 African Americans (AA), three Hispanics and one Asian. Inclusion criteria for healthy controls were: (1) absence of past or present neurological or psychiatric illnesses; (2) no concomitant or past severe medical conditions; (3) no pregnancy.…”

“…[10][11][12][13] The A1 allele was also found to be associated with prolonged P300 latency, reduced visuospatial preference, and low cerebral glucose utilization, all putative markers of alcoholism and dopamine function deficiency. [15][16][17] In addition, the A1 allele has also been associated with substance abuse, [6][7][8][9] which led to its conceptualization as a 'reward gene'. Together, these data suggest that this polymorphism might affect dopamine transmission in a way that predisposes subjects to 'reward seeking' behavior, i.e.…”

Alcohol y cerebro adolescente

“…Entre estas variables críticas fuentes de confusión conviene destacar especialmente la falta de control de vulnerabilidad genética, presencia de trastornos psicológicos y los efectos del consumo de otras sustancias psicoactivas. En cuanto a la vulnerabilidad genética, un buen numero de estudios, entre los que se encuentra nuestra propia investigación, han encontrado de forma consistente diferencias neuropsicológicas y psicofisiológicas entre niños procedentes de familias con alta densidad de alcoholismo y sus controles de bajo riesgo, especialmente en tareas que implican memoria de trabajo y capacidades visuoespaciales 43,[48][49][50] , procesos que se ha informado están afectados por el patrón BD. También es común en los estudios sobre patrón BD ausencia de control en las muestras de trastornos psicológicos, especialmente depresión o trastornos de alimentación en mujeres y trastornos de conducta en hombres 51 .…”