Brief Answer:
Mostly genetic and adolescence has some effects on it

Detailed Answer:
Hi! Welcome to Healthcaremagic. Thanks for sharing your concerns with us. We will try to help you in best way possible.

Based on the history you have shared, mostly the causes are genetic as touretts have tendency to pass on the condition in next generations and in some cases 50 percent children are affected. The exact genetic pattern is under research and not clear yet. Other factors like envoirnment ans social stressers play an important role. Rarely autoimmune etiology has been hypothesized but yet not proven. The autoimmune causes are thought to be triggered by strep infections in children but again this is not widely accepted.

Adolescence has role in the symptoms, not directly but indirectly. Hormonal changes lead to behavior changes and multiple social stressers and peer pressures put effects on the intensity of the symptoms. The clinical presentations are usual mild and often go unnoticed but the severe cases though rare are mostly evident after adolescence so it's where the relationship comes in.

Hope this has answered your query. If you have any more questions please feel free to ask. Regards

---