Although CBCL-anxiety was significantly associated with SCQ in the overall model, results regarding the effects of OXTR on SCQ scores were otherwise unchanged [rs53576 in ASD: OR = 1.4 (1.1–1.7), rs53576 in ADHD: OR = 0.8 (0.6–0.9), rs53576*dx: p < 0.0001; rs2254298 in ASD: OR = 1.3 (1.1–1.5), rs2254298 in ADHD: OR = 0.7 (0.6–0.8), rs2254298*dx: p < 0.001]. This evidence concerns the gene OXTR and attention deficit-hyperactivity disorder.