In a recent article, Erenberg and Fahn1 presented reasons why they prefer the Tourette Syndrome Association classification of tic disorders2 to that of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV).3 Other authors4,5 have similarly expressed reservations about the DSM-IV criteria. We agree with the points raised by Erenberg and Fahn and now present additional concerns about the DSM-IV criteria and provide an alternative classification scheme that we believe is more consistent with current information and is more appropriate for application to genetic studies. Accurate phenotypic diagnosis is crucial to our current research efforts to localize the genetic defects of Tourette syndrome (TS).
1. Vocal tics are sounds produced by moving air through the nose, mouth, or throat.2 The movement of air and the production of sounds are accomplished by the contraction of muscles of the mouth, tongue, pharynx, larynx, diaphragm, and