"23andMe and our third party genotyping laboratory will retain your genetic information, date of birth, and sex as required for compliance with applicable legal obligations, including the U.S. Federal Clinical Laboratory Improvement Amendments of 1988 (CLIA), California Business and Professional Code Section 1265, and College of American Pathologists (CAP) accreditation requirements.

23andMe will retain limited information related to your data deletion request, such as your email address and Account Deletion Request Identifier, as necessary to fulfill your request and for the establishment, exercise or defense of legal claims."

So they'll retain your DNA info and personally identifying info that you provided, forever. But the physical sample will be destroyed.