While the presence of putative toxic metals increased in ASD patients (ASD1) is sufficient to significantly increase GluN2b expression levels, GluN1 and GluN2a and Shank1, Shank2, and Shank3 mRNA levels are only significantly altered in case of an additional Zn and Fe deficiency (ASD2). The gene discussed is SHANK2; the disease is atrial septal defect 2.