WASHINGTON - As a White House aide in 1971, Republican presidential candidate Patrick Buchanan suggested in a memo to President Nixon that efforts to integrate the U.S. might only result in "perpetual friction" because blacks and the poor may be genetically inferior to middle-class whites.

Buchanan said yesterday he does not believe blacks are genetically inferior to whites and did not have that belief in the past.

Buchanan said he sent the memo to Nixon as a routine matter of intellectual curiosity.

"No, that is nonsense," Buchanan said, when asked if his words represent a belief in the genetic superiority of whites. "I tell you what I did for Nixon, all the way through his White House, and for Ronald Reagan too. They asked for articles each week on controversial pieces they wanted or needed to see."

The memo to Nixon was prompted by the September 1971 issue of The Atlantic, in which author Richard Herrnstein argued that the devotion of government resources to compensatory education and other anti-poverty programs would not result in a more equitable society. The more that government removed social barriers, Herrnstein wrote, the more that genetically blessed individuals would rise to the top of a caste system based on merit.

"Basically, it demonstrates that heredity, rather than environment, determines intelligence - and that the more we proceed to provide everyone with a `good environment,' surely the more heredity will become the dominant factor - in their intelligence, and thus in their success and social standing," Buchanan wrote to Nixon. " It is almost the iron law of intelligence that is being propounded here - based on heredity.

"The importance of this article is difficult to understate. If correct, then all our efforts and expenditures not only for `compensatory education' but to provide an `equal chance at the starting line' are guaranteeing that we wind up with the intelligent ones coming in first. And every study we have shows blacks 15 IQ points below whites on the average."

Buchanan also warned Nixon that, as Herrnstein noted, the ultimate conclusion of the thesis - that some groups or races are inherently superior to others - carried "rather frightful" political implications.