Over the last few years, there has been increasing interest in autoimmunity to the cerebral folate receptor, with findings suggesting that around 50% of the ASD cases are positive for these auto-antibodies. It is thought that auto-antibodies to the cerebral folate receptor block the transport of folic acid into the cerebrospinal fluid, leading to low 5MTHF (5-methyltetrahydrofolate), the form of folate that is used in the central nervous system and could account for some of the neurological symptoms observed in ASD.

Cerebral folate deficiency has been associated with mental retardation, movement disorders, epilepsy, speech and communication disorders, but it is unclear at the moment how prevalent the issue is across the whole autism spectrum. However, we must stress that the biochemical processes implicating folic acid have been found to be commonly abnormal in autism: methylation and transulfuration (1). Equally, there is very good outcomes with a related therapy using methyl-cobalamin (vitamin B12) (2).

A study published in 2007 by Ramaekers et al (3) identified 19 patients in a group of 23 low-functioning autistic children presenting with neurologocial deficits who were found to be positive for folate receptor auto-antibodies. The authors reported good outcome to remedial treatment with folic acid. Other reports have been made and confirmed an implication for a significant proportion of children with autism (4).

There is no cost involved in testing the children. The study has received ethical approval from the University of Texas and no further ethical requirement is required at this end.

The Autism Treatment Trust has the opportunity to test for the presence auto-antibodies to cerebral folate receptors with the support of Professor Richard Finnell, Department of Nutritional Sciences, Chemistry and Biochemistry, at the University of Texas at Austin.
We are now ready to proceed with the study and should be in the position to send 20 samples to Texas in January. We will update you on the outcomes of the study in or next newsletter.

Prof. Richard Finnell is visiting the Edinburgh in January and we are hoping for him to give a short presentation on his work at the Autism Treatment Trust. Please check our web site for updates.

Richard Finnell

Professor, Departments of Nutritional Sciences, Chemistry and Biochemistry
Director, Genomic Research, Dell Children’s Medical Center
Ph.D, 1980, University of Oregon Medical School

Dr. Finnell’s research examines the interaction between specific genes and environmental toxins as they influence normal embryonic development. While his primary research focuses on discovering the role of folic acid in the prevention of birth defects, his laboratory is also working to identify the gene or genes that determine susceptibility to human neural tube defects (NTDs) and orofacial clefts. Dr. Finnell is studying teratogenic agents, both pharmaceutical compounds and those found in the environment, that contribute to the population burden of birth defects.

References:

(1)  Main PA, Angley MT, Thomas P, O’Doherty CE, Fenech M. Folate and methionine metabolism in autism: a systematic review.

Am J Clin Nutr. 2010 Jun;91(6):1598-620. Epub 2010 Apr 21.

(2) James SJ, Cutler P, Melnyk S, Jernigan S, Janak L, Gaylor DW, Neubrander JA. Metabolic biomarkers of increased oxidative stress and impaired methylation capacity in children with autism. Am J Clin Nutr. 2004 Dec;80(6):1611-7. http://www.ncbi.nlm.nih.gov/pubmed?term=Neubrander%20autism%20James.

(3) Ramaekers VT et al. Folate Receptor Autoimmunity with Cerebral Folate Deficiency in Low-Functioning Autism with neurological deficits.  Neuropediatrics 2007; 38: 276 – 281.

(4) Dr Bradstreet 2011.