Joseph Murin, the president of government-run mortgage bond insurer Ginnie Mae, will step down tomorrow after about 13 months on the job, according to two people familiar with his plans.

Murin, who joined Ginnie Mae on July 1, 2008, plans to pursue private business opportunities, according to the people, who asked not to be named because an announcement has yet to be made. Before becoming Ginnie Mae’s president, Murin was president of Mortgage Settlement Network LLC, a Pittsburgh-based provider of loan settlement services and appraisals.

His resignation would be the third departure this year of the top executive for the main companies responsible for the majority of U.S. mortgage financing. Freddie Mac CEO David Moffett resigned in March, and Herb Allison left Fannie Mae to help oversee a $700 billion bank rescue program.
Ginnie Mae, which helped to pioneer the mortgage-backed securities market in 1970, mainly guarantees payments on bonds backed by loans insured by the Federal Housing Administration, Veterans Affairs Department or Agriculture Department.
The agency, which issues the only mortgage bonds to carry the “full faith and credit” of the U.S. government, packaged a record $43.5 billion in federally backed loans into securities in June. The agency’s mortgage bond volume almost doubled in the first half of this year, to $207 billion from $107 billion during the same timeframe a year ago, as the mortgage markets seized and borrowers turned to federally supported mortgage financing.

Mortgage bonds guaranteed by U.S. agency Ginnie Mae will probably swell to $1 trillion by the end of 2010 because borrowers with low down payments or credit scores can only qualify for government-insured loans, Bank of America Corp. analysts said.

The Federal Housing Administration, which insures loans with down payments as low as 3.5 percent and has no credit-score requirements, is “the only source of funding for these leveraged borrowers,” Ankur Mehta and Ohmsatya Ravi, the New York-based analysts, wrote in a report yesterday.