Letters Section Editor: Jody W. Zylke, MD, Senior Editor.
Author Affiliations: Norwegian Institute of Public Health, Oslo, Norway (Drs Surén and Stoltenberg) (firstname.lastname@example.org); and Mailman School of Public Health, Columbia University, New York, New York (Dr Susser).
In Reply: The studies referred to by Drs Vahabzadeh and McDougle identified signs of aberrant folate-dependent metabolism and an increased occurrence of folate receptor autoantibodies in children with autism spectrum disorders. We agree that investigations of these mechanisms should be a priority in future research on autism spectrum disorders. However, they are just 2 of several potential explanations.
Folate is a vital co-factor in DNA synthesis, DNA repair, and DNA methylation, and there are multiple ways in which fetal brain development could potentially be influenced by a lack of folate or a reduced ability to use available folate. Consequently, the analytic approach has to be broad and include both genetic and epigenetic analyses, as well as analyses of folate and other related metabolites in blood plasma.
Surén P, Susser E, Stoltenberg C. Maternal Folic Acid Supplementation and Risk of Autism—Reply. JAMA. 2013;309(21):2208. doi:10.1001/jama.2013.4879