Yale Researchers Discover Tourette Syndrome Gene Mutation

Researchers at Yale University, led by Matthew State, MD, professor of psychiatry and genetics, have discovered a rare mutation in a gene through their work with a family with Tourette syndrome (TS). Discovery of this mutation could lead to a novel approach to the treatment of TS.

The family that Slate and his research team worked with included a mother, father, and eight offspring. Everyone in the family, except the mother, suffer from TS; the father and two of the children also had obsessive-compulsive disorder. Through DNA analysis, the researchers found that one region of the genome was affected in all family members with TS, a discovery that then led to the identification of a rare mutation in the 1-histidine de carboxylase (HDC) gene, which makes a protein that is required for the production of histamine. The mutation in this gene resulted in the mutated protein losing its function.

“Rare families have been used in a variety of other common conditions to help identify underlying mechanisms of disease and find new approaches to treatment,” said Adife Gulhan Ercan-Sencicek, post-doctoral fellow, Yale University, and lead author of the associated New England Journal of Medicine article. “We thought we could use the same approach in Tourette syndrome.”

According to State, previous research on brain histamine in other labs revealed that mice with low levels of this amine are more likely to exhibit repetitive behaviors that are similar to human tics. Increasing brain histamine in these animals reversed the problem.

“The opportunity to go directly from a rare genetic finding to a trial of a new approach to treatment in a neuropsychiatric disorder is very unusual,” said State. “We were lucky to happen across a gene pointing to a well-studied area in neuroscience. There are several new medications in development that increase the release of brain histamine. Based on this genetic finding, these compounds would be good candidates for new treatments for Tourette.”