These securities are issued by government agencies rather than by the U.S. Treasury. Those agencies include the Student Loan Marketing Association (Sallie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), the Federal National Mortgage Association (Fannie Mae), and the Government National Mortgage Association (Ginnie Mae), among others. These securities are backed by the government, though not guaranteed by the government, and as a result, have a slighter higher level of risk associated with them when compared to Treasury securities.