Elsevier

Neuroscience Letters

Volume 422, Issue 1, 5 July 2007, Pages 24-29
Neuroscience Letters

Preliminary evidence for involvement of the folate gene polymorphism 19 bp deletion-DHFR in occurrence of autism

https://doi.org/10.1016/j.neulet.2007.05.025Get rights and content

Abstract

Folate has long been implicated in both the metabolism of neurotransmitter molecules, and as an agonist with a direct effect upon neuronal tissue. Folates mediate transfer of one-carbon units into major biosynthetic pathways. From a developmental perspective, the most important reactions are de novo methionine and thymine synthesis, critical for DNA expression and elaboration, respectively. Dihydrofolate reductase (DHFR) is the sole enzyme responsible for maintaining the reduced state of the vitamin needed for these two pathways. Here, we report that the 19 bp-deletion polymorphism of DHFR acts independently (OR 2.69, 95% CI; 1.00–7.28, p < 0.05) and in concert with related folate polymorphisms as a significant risk factor for autism. Possible consequences of this are discussed in the context of the interaction between folate and the glutamatergic nervous system, an area of promising candidate genes for contributing to autism.

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Acknowledgements

This work was funded by Hunter Children's Research Foundation and the Faculty of Science & IT, University of Newcastle, Australia.

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