Zinc deficiency and supplementation in autism spectrum disorder and Phelan-McDermid syndrome

Approximately 1 in 36 children are diagnosed with autism spectrum disorder (ASD). The disorder is four times more common in males than in females. Zinc deficiency and mutations in SHANK2 and SHANK3 (members of a family of excitatory postsynaptic scaffolding proteins) are all risk factors that may contribute to the pathophysiology of the disease. The presence of shankopathies (loss of one copy of the SHANK3 gene) can lead to the development of Phelan-McDermid syndrome (PMDS)-a rare genetic disorder characterized by developmental delay, intellectual disability, poor motor tone, and ASD-like symptoms. We reviewed the relationship between zinc, ASD, and PMDS as well as the effect of zinc supplementation in improving symptoms of ASD and PMDS based on 22 studies published within 6 years (2015-2020). Zinc deficiency (assessed by either dietary intake, blood, hair, or tooth matrix) was shown to be highly prevalent in ASD and PMDS patients as well as in preclinical models of ASD and PMDS. Zinc supplements improved the behavioral deficits in animal models of ASD and PMDS. Clinical trials are still needed to validate the beneficial therapeutic effects of zinc supplements in ASD and PMDS patients.

Automated summary

Approximately 1 in 36 children are diagnosed with autism spectrum disorder (ASD) and the disorder is four times more common in males. Risk factors for ASD include zinc deficiency and mutations in SHANK2 and SHANK3 genes. The loss of SHANK3 gene can lead to the development of Phelan-McDermid syndrome (PMDS), which is characterized by developmental delay, intellectual disability, and ASD-like symptoms. Zinc deficiency is prevalent in ASD and PMDS patients as well as in preclinical models. Zinc supplementation has shown to improve behavioral deficits in animal models but further clinical trials are needed to validate its therapeutic effects in ASD and PMDS patients.