SAN FRANCISCO - Google Inc. loves 23andMe Inc., a biotechnology startup conceived by co-founder Sergey Brin's wife.

In its latest showing of financial affinity, Google disclosed Thursday that it has invested another US$2.6 million in a company that analyzes people's DNA to detect potential health problems before they occur.

Anne Wojcicki, who married Brin two years ago, started 23andMe while the couple was still dating.

Just a few weeks after Brin's marriage, Google announced that it had bought a minority stake in 23andMe for $3.9 million. The Internet search leader placed another $500,000 in 23andMe in late 2007.

Part of Google's original investment was used to repay $2.6 million in financing that Brin had provided 23andMe.

Since then, Brin has also used a sliver of his $12-billion fortune to invest about $10 million in his wife's venture, according to Google's filing with the Securities and Exchange Commission.

Brin, 35, discovered from a 23andMe scan that he carries a genetic mutation increasing his risk of developing Parkinson's.

Google's decision to invest in a startup near and dear to Brin hasn't yet raised complaints about nepotism among the Mountain View-based company's major shareholders.

The $7 million that Google has invested in 23andMe barely dented the Internet search leader's bank account. Google had nearly $18 billion in cash and marketable securities at the end of March.

Besides its investment, Google also agreed to lease some of its office space to 23andMe, which also is based in Mountain View.