Showing papers by "Miguel Ángel Jiménez-Arriero published in 2009"
TL;DR: Current data show that the TaqIA polymorphism may be a marker of both DRD2 and ANKK1 genetic variants, which raises the question of whether signaling players intervene in the pathophysiology of psychiatric disorders.
Abstract: The TaqIA single nucleotide polymorphism (SNP, rs1800497), which is located in the gene that codes for the putative kinase ANKK1 (ANKK1) near the termination codon of the D2 dopamine receptor gene (DRD2; chromosome 11q22-q23), is the most studied genetic variation in a broad range of psychiatric disorders and personality traits. A large number of individual genetic association studies have found that the TaqIA SNP is linked to alcoholism and antisocial traits. In addition, it has also been related to other conditions such as schizophrenia, eating disorders, and some behavioral childhood disorders. The TaqIA A1 allele is mainly associated with addictions, antisocial disorders, eating disorders, and attention-deficit/hyperactivity disorders, while the A2 allele occurs more frequently in schizophrenic and obsessive-compulsive patients. Current data show that the TaqIA polymorphism may be a marker of both DRD2 and ANKK1 genetic variants. ANKK1 would belong to a family of kinases involved in signal transduction. This raises the question of whether signaling players intervene in the pathophysiology of psychiatric disorders. Basic research on the ANKK1 protein and its putative interaction with the D2 dopamine receptor could shed light on this issue.
86 citations
TL;DR: Brain areas involved in the visual and auditory versions of the n-back task showed an important overlap between them, reflecting the supramodal characteristics of working memory.
53 citations
TL;DR: It is suggested that the Val158Met SNP is involved in risk and protective genotypes for the vulnerability to schizophrenia in Spanish male population.
Abstract: The functional Val158Met polymorphism (rs4680) located at the gene that codes for the catechol-O-methyltransferase (COMT) has been extensively investigated in schizophrenia although current data are still controversial. Since COMT activity is sexually dimorphic, we carried out two independent studies in homogeneous samples of male and female Spanish schizophrenic patients. In males, we found an association between the homozygous Val genotype and the disorder, which resembled a recessive model (P = 0.022; odds ratio [OR] = 1.67). This Val homozygotes overrepresentation is produced at the expense of the heterozygous individuals decrease, whilst the Met homozygotes showed no differences when compared controls and patients. As a consequence, the heterozygous genotype in this sample had a protective effect (P = 0.03; OR = 0.65) and a strong deviation from Hardy–Weinberg equilibrium in male cases was observed (P = 0.006). In addition, a 2-SNP haplotype analysis (rs4818-Val158Met) confirmed there is an overrepresentation of the different homozygous Val genotypes in the male schizophrenic sample. Regarding females, we did not find any statistically significant association between COMT SNP and schizophrenia. In the light of this we suggest that the Val158Met SNP is involved in risk and protective genotypes for the vulnerability to schizophrenia in Spanish male population. © 2009 Wiley-Liss, Inc.
53 citations
TL;DR: It is concluded that hypofrontality during cognitive activation, and the degree of DLPF structural deficit may be associated to a particular profile of cognitive deficit, including lower processing speed and working memory capacity.
Abstract: The possible association in schizophrenia between frontal abnormalities, such as hypofrontality and frontal grey matter (GM) deficits, and neuropsychological deficits is not yet well defined Our objective was to study such an association and to clarify the cognitive relevance of metabolic and anatomical variability across schizophrenia patients To do so, we studied dorsolateral prefrontal (DLPF) metabolism during an attention test using fluoro-deoxy-glucose positron emission tomography and DLPF structure with magnetic resonance imaging (MRI) in 22 schizophrenia patients [9 neuroleptic-naive (NN) first episodes] These patients also underwent a comprehensive battery of neuropsychological tests aimed at evaluating global intelligence and the proposed domains of cognitive alteration in schizophrenia, ie, attention, visual and verbal learning and memory, working memory, problem solving and processing speed The metabolic activity in the right DLPF region was significantly and directly related to processing speed, and a measure of structural deficit in the same area was directly related to working memory scores In the NN group studied alone, these associations were replicated We may conclude that hypofrontality during cognitive activation, and the degree of DLPF structural deficit may be associated to a particular profile of cognitive deficit, including lower processing speed and working memory capacity
29 citations