TNF and attention deficit-hyperactivity disorder: Moreover, a study addressing the association between ADHD and polymorphism of TNF-α genes in children with ADHD and healthy controls showed that the 308 polymorphism (alleles 1 and 2) at the TNF-α gene is correlated with two attention measures, the hand-eye test of the Neurobehavioral Evaluation System (NES2), which evaluates visual-motor coordination, and sub-test of Shape Discrimination Test (TDTP) [58].