I don't know about 23andme, but I have read Privacy Policies of similar services in the past and they are all riddled with legalese and unclear phrasing that make using the service a complete no-go for me.

Also note that if the policy seems clear you have to follow and read the PP's of their partners and 3rd-parties, and then their partners, etc.

IANAL and you should be before bestowing your trust in such service, unless you don't mind having your DNA profile out in the open.