This is not at all similar. It would be highly surprising to me to find that long-term exposure to ritalin leads to deletions and copy number variations in some

This is not at all similar. It would be highly surprising to me to find that long-term exposure to ritalin leads to deletions and copy number variations in someone's DNA. Furthermore, it is improbable that a drug causing DNA changes would cause the same changes across a population in a statistically significant way. Can you point me to any research that shows this to be the case?