Associations between the tumor necrosis factor alpha gene (-308G→A) and event-related potential indices of attention and mental rotation.

The tumor necrosis factor alpha (TNF-α) is a cytokine that exerts neuroprotective and neurodegenerative effects. While some research suggests enhancing effects of the TNF-α gene (TNF-α -308G→A) on cognitive function, further research is needed to clarify the association between the TNF-α gene and specific areas of cognitive performance including their neurophysiological correlates. In this study we examine association of the TNF-α -308G→A single nucleotide polymorphism (rs1800629) with attention and mental rotation performance in an event-related potential (ERP) study in healthy participants (n=67). The results show that carriers of the -308 A allele display elevated attentional processes (i.e. a stronger N1) as compared to the GG genotype group. Mental rotation performance varied across genotypes when demands on mental rotation were high. Here, carriers of the -308 A allele performed better than the GG genotype group. This is paralleled by the neurophysiological data showing genotype-dependent variations in parietal positivities only under the condition of high demands on mental rotation. The finding of enhanced attentional and mental rotation performance in A allele carriers supports recent findings that the A allele of this single nucleotide polymorphism (SNP) enhances cognitive performance on a general measure of cognitive processing speed.