Variable-rate mortgages permitted

National banks throughout the country Tuesday were given the right -- starting immediately --Two consumer groups criticized the system, saying it could make it impossible for many Americans of modest means to own homes. Comptroller of the Currency John G. Heimann issued final regulations that override state laws and allow national banks to issue so-called "adustable rate" mortgages.

Instead of the home buyer's paying, say, 15 percent annual interest for 20 or 30 years, the mortgage rate would -- within limits -- rise and fall with interest rates in financial markets. The rate could rise no more than one percentage point each six months, but there would be no total limit on how much it could rise or fall over the years. Banks will not be required to increase mortgage rates when financial rates rise, but they have that option. They will, however, be required to lower the mortgage rate when financial rates fall.