President Reagan said in an interview published Friday he believes Soviet leader Mikhail Gorbachev had been baptized a Christian but that during four summits they had never had a chance to discuss religion. In remarks published by the London Daily Telegraph, Reagan said that although Gorbachev makes frequent references to God, the president had been unable to establish during the Moscow summit whether the leader of the officially atheist Soviet Union was a believer. "I've never had the opportunity to discuss that with him or to know whether he is (a believer) or not," Reagan was quoted as saying. Reagan said that according to material he had read, Gorbachev, born in 1931, 14 years after the communist revolution, had been baptized at the insistence of his mother.