What genetic inheritance pattern is associated with Tourette syndrome?

Tourette syndrome is primarily associated with an autosomal dominant inheritance pattern. This means that only one copy of the mutated gene, inherited from one parent, is sufficient to cause the disorder. This pattern often results in affected individuals having a 50% chance of passing the condition to their offspring. Family studies have shown that Tourette syndrome frequently runs in families, which supports the notion of a genetic predisposition under this inheritance model.

In addition to the genetic aspect, familial aggregation and the presence of other tic disorders or associated comorbidities, such as obsessive-compulsive disorder and attention deficit hyperactivity disorder, are commonly seen in relatives of affected individuals, further supporting the autosomal dominant nature.

This genetic understanding contrasts with autosomal recessive conditions, where two copies of the mutated gene must be inherited (one from each parent) for the disorder to manifest. In X-linked inheritance patterns, the gene is located on the X chromosome, which primarily affects males while females are usually carriers. Mitochondrial inheritance involves genes located in mitochondrial DNA, which is passed down exclusively through the maternal line, and is not applicable to Tourette syndrome. Thus, the autosomal dominant pattern remains the most fitting characterization for Tourette syndrome's inheritance.