Genealogy website Ancestry.com Inc. ACOM -1.68% has agreed to be acquired by an investor group led by European private-equity firm Permira for about $1.6 billion, or $32 a share, according to people familiar with the deal.

The buyout is a bet that family-history research is more than a niche market and that the subscriber base can swell with technological innovations, deeper archives and a wider international audience. People familiar with the buyers' plans said that expansion in western Europe is a goal. Report: Ancestry.com Acquired By Investor Group, Permira, For $1.6 Billion [online.wsj.com]