RESUMO
Normal and pathologic neurobiological processes influence brain morphology in coordinated ways that give rise to patterns of structural covariance (PSC) across brain regions and individuals during brain aging and diseases. The genetic underpinnings of these patterns remain largely unknown. We apply a stochastic multivariate factorization method to a diverse population of 50,699 individuals (12 studies and 130 sites) and derive data-driven, multi-scale PSCs of regional brain size. PSCs were significantly correlated with 915 genomic loci in the discovery set, 617 of which are newly identified, and 72% were independently replicated. Key pathways influencing PSCs involve reelin signaling, apoptosis, neurogenesis, and appendage development, while pathways of breast cancer indicate potential interplays between brain metastasis and PSCs associated with neurodegeneration and dementia. Using support vector machines, multi-scale PSCs effectively derive imaging signatures of several brain diseases. Our results elucidate genetic and biological underpinnings that influence structural covariance patterns in the human brain.
Assuntos
Neoplasias Encefálicas , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/patologia , Mapeamento Encefálico/métodos , Genômica , Neoplasias Encefálicas/patologiaRESUMO
Objective:To assess the relationship between cognitive function, a proposed schizophrenia endophenotype, and two genetic polymorphisms related to dopamine function, catechol-O-methyl transferase (COMT) Val158Met and dopamine receptor 3 (DRD3) Ser9Gly.Methods:Fifty-eight outpatients with schizophrenia/schizoaffective disorder and 88 healthy controls underwent neurocognitive testing and genotyping. Analyses of covariance (ANCOVAs) using age, sex, and years of education as covariates compared cognitive performance for the proposed genotypes in patients and controls. ANCOVAs also tested for the epistatic effect of COMT and DRD3 genotype combinations on cognitive performance.Results:For executive functioning, COMT Val/Val patients performed in a similar range as controls (30.70-33.26 vs. 35.53-35.67), but as COMT Met allele frequency increased, executive functioning worsened. COMT Met/Met patients carrying the DRD3 Ser/Ser genotype performed poorest (16.184 vs. 27.388-31.824). Scores of carriers of this COMT/DRD3 combination significantly differed from all DRD3 Gly/Gly combinations (p < 0.05), from COMT Val/Met DRD3 Ser/Gly (p = 0.02), and from COMT Val/Val DRD3 Ser/Ser (p = 0.01) in patients. It also differed significantly from all control scores (p < 0.001).Conclusion:Combined genetic polymorphisms related to dopamine neurotransmission might influence executive function in schizophrenia. Looking at the effects of multiple genes on a single disease trait (epistasis) provides a comprehensive and more reliable way to determine genetic effects on endophenotypes.
Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Catecol O-Metiltransferase/genética , Cognição/fisiologia , Epistasia Genética , Polimorfismo de Nucleotídeo Único , /genética , Esquizofrenia/genética , Análise de Variância , Estudos de Casos e Controles , Escolaridade , Função Executiva/fisiologia , Frequência do Gene , Estudos de Associação Genética , Testes Neuropsicológicos , Reação em Cadeia da Polimerase em Tempo Real , Esquizofrenia/fisiopatologiaRESUMO
Baseados neste e demais estudos da literatura evidencia-se que a ressecção cirúrgica de áreas epileptogênicas localizadas ocupa um lugar importante no tratamento das eplepsias. Para tanto, a localização dos focos deve ser precisa, devendo situar-se em área cerebral cirurgicamente acessível, por ser possível sua excisão sem consequências...