wie viel kostet ein allergietest — what are common causes?

The provided context does not contain any information about the cost of allergy tests or common causes of allergies. The context focuses on DNA tests for metabolism and sports genetics, not allergy diagnostics. Without relevant sources, I cannot provide evidence-based answers. For reliable information on allergy testing (e.g., skin prick test, specific IgE) and common triggers (pollen, dust mites, foods), please consult an allergist or official guidelines.