where ginnie mae guarantees only securities that comprise mortgages guaranteed by federal agencies such as the fha and va its relatives may back securities whose mortgages are not insured by the government fannie mae has a portfolio that invests in its own and other institutions mortgage backed securities 
the gnma is also ostensibly the only mae or mac backed by the full faith and credit of the federal government in 2008 during the housing crisis fannie mae and freddie mac were overseen by the government via a conservatorship of the federal housing finance committee 9 some argue that the bailout erased ginnie mae s distinction as the only federal agency guaranteeing mortgage securities that enjoy government protection against failure 