Regeneron said Monday it will “prioritize the privacy, security and ethical use” of the personal DNA data from about 15 million people in a $256 million deal to acquire assets of bankrupt 23andMe Holding Co.

But, more concerning than the success or failure of a particular company, was this question: What would happen to 23andMe's vast trove of highly personal customer data? We aren't just talking about usernames and birthdays.

Regeneron announced a plan to acquire genetic testing firm 23andMe through bankruptcy court, including access to personal genetic data. What to know