Google is pouring more into a biotech startup led by co-founder Sergey Brin's wife, according to a regulatory filing on Friday.

In its latest show of support, Google's venture capital arm invested $1.5 million in 23andMe Inc., which launched in 2007 — the same year that Brin married the startup's co-founder and CEO, Anne Wojcicki.

This marks the fourth time in the past five years that Google Inc. has helped fund 23andMe's ambitions to create a viable business that analyzes people's DNA to flag potential health problems before they occur. Google has invested a total of $11.7 million in 23andMe, including $500,000 that bought stock from another early shareholder in 2007. 23andMe also leases its office space from Google, which is based in Mountain View, Calif.

Brin, whose wealth is estimated at nearly $19 billion by Forbes magazine, also has personally invested at least $10 million in 23andMe, based on Google's past disclosures.

Besides being married to Brin, Wojcicki is the sister of a top Google executive, Susan Wojcicki, who rented part of her garage to Google when it was just starting out in 1998.

Google's audit committee approved the latest investment in 23andMe

As of Sept. 30, Google had $47 billion in cash. The company's venture capital arm has backed more than 150 companies so far and aims to invest about $300 million annually.