Table 2. Risk factors associated with ADHD symptoms.

Genetic risk factors

Dopamine receptor genes (DRD4, DRD5)
Dopamine transporter gene (DAT1)
Gene encoding O methyl transferase (COMT)
Non-genetic/environmental risk factors
Adversity
Low socioeconomic status
Victimization
Child-parent attachment
Family discord
Intra/interpersonal violence exposure
Toxin exposure
Lead
Organophosphate pesticides
Polychlorinated biphenyls
Prenatal
Maternal cigarette smoking
Maternal alcohol use
Maternal stress
Maternal use of illicit drugs
Perinatal
Prematurity
Low birth weight
Nutritional
Sugar
Zinc
Food colorings
Magnesium
Polyunsaturated fatty acids (omega-3)

ADHD, attention-deficit/hyperactivity disorder.