23andMe: Profiles of 6.9 million people hacked
In some cases this included family trees, birth years and geographic locations, the company said.
After weeks of speculation the firm has put a number on the breach, with more than half of its customers affected.
The stolen data does not include DNA records.
23andMe is a giant of the growing ancestor-tracing industry. It offers genetic testing from DNA, with ancestry breakdown and personalised health insights.