Richard Deth - Research Focus

Research Focus

The primary realm of research conducted by Deth involves the role of D4 dopamine receptors in schizophrenia and attention. He has focused on understanding the molecular basis of transmembrane signaling by G protein-coupled receptors, the study of their structure using three-dimensional molecular graphics, and modeling how the binding of various drugs causes a shift in their molecular form.

Deth has characterized the conformation-dependent participation of D4 dopamine receptors in the process of phospholipid methylation, and found that different states of methylation yield varying degrees of spontaneous activity of G protein coupling. He has theorized that these processes are involved in the neural mechanisms of attention. Deth has found that insulin-like growth factor-1 (IGF-1) and dopamine both stimulated folate-dependent methylation pathways in neuronal cells, while compounds like ethanol, the vaccine preservative thimerosal, and metals (like mercury, which is contained in thimerosal, and lead) inhibited these same biochemical pathways at low concentrations resembling those found following vaccination or other sources of exposure. An enzyme mediating methylation, methionine synthase, uses an active form of vitamin B₁₂ to complete its chemical function. Thimerosal interferes with the conversion of dietary forms of B₁₂ into the active form and so impedes DNA methylation and disrupts mercury detoxification and some normal gene actions.

Based on this research, Deth has theorized that thimerosal in vaccines could give rise to autism in a subset of children who are genetically vulnerable. He has played an active role in the thimerosal controversy, testifying twice to Congress about his views. Deth's hypothesis is, however, contradicted by much of the current literature about the causes of autism, which indicates that the levels of thimerosal found in vaccines and other sources cannot be directly implicated as a cause.