The investigation into a $50 million mortgage fraud scam involving three lawyers, a Manhattan dominatrix club and dozens of Long Island properties is expected to grow larger today with additional charges and additional defendants, a spokesman for Suffolk County District Attorney Thomas J. Spota said.

The operation allegedly recruited straw buyers at the dominatrix club Arena Studio to obtain fraudulent home mortgages and has snared attorney George O. Guldi, who was a Democratic Suffolk County legislator until 2003.