A House Democrat yesterday distributed copies of a memo allegedly written by a Republican consultant asserting that the GOP could exploit the AIDS issue in the 1988 congressional campaign, but the man alleged to be the memo's author said it was a fabrication.

Rep. Howard Wolpe (D-Mich.) said he obtained the memo and an accompanying list of 53 targeted House members. He circulated it among those allegedly targeted for defeat. The alleged memo concludes that, if properly exploited, the issue of acquired immune deficiency syndrome could "help us to gain ground in '88" and also "help us hang on where some of our people are in trouble."

In a "Dear Colleague" letter, Wolpe said the memo had been written by Charles Rund, a San Francisco-based political consultant and a deputy pollster for President Reagan's 1984 reelection campaign.

Rund, contacted last night, said the memo is "all a fabrication -- it's just not true."

"I just think it's reprehensible the Democrats" would distribute the document, Rund said. "That is not a memo written by me or associated with me."

Rund acknowledged that he prepared the list of targeted House members, including House Majority Leader Thomas S. Foley (D-Wash.). But he described it as an internal list of potentially "hot races" that he and his employes at Charlton Research Co. will attempt to become involved in.

But he said it had nothing to do with AIDS.