EXHIBIT 16.1

February 16, 2007

Securities and Exchange Commission

100 F Street N.E.

Washington, D.C. 20549

We have been furnished with a copy of the response to Item 4.01 of Form 8-K for the event that occurred on February 15, 2007 to be filed by our former client, BioTime, Inc. We agree with the statements made in response to that Item insofar as they relate to our Firm.

Very truly yours,

/s/ BDO Seidman, LLP