(CNN) -- Uganda's President has said he's seeking advice from American scientists before he decides whether to sign a bill that criminalizes homosexuality. Homosexual acts are illegal in Uganda. The proposed legislation passed by parliament toughens the penalties, including life imprisonment for certain acts. President Yoweri Museveni 's decision backtracks from his announcement last week, when he said he'd sign the bill for "scientific" reasons. At the time, he said that Ugandan scientists had determined there was no gene for homosexuality. "It was learned and could be unlearned," he said. Shortly after his announcement, U.S. President Barack Obama warned that enacting the bill would affect relations between the two nations. He described the proposal as an "affront and a danger to the gay community" in Uganda.
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Last week, President Yoweri Museveni said he would sign a bill that criminalizes homosexuality
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The bill has been debated in Uganda for years
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President Barack Obama said enacting the bill would affect U.S. relations with Uganda
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This week, Museveni says he's seeking advice from U.S. scientists
"I therefore encourage the @placeholder government to help us by working with our scientists to study whether, indeed, there are people who are born homosexual," Museveni said.