Cuba's prevailing religion is Christianity, primarily Roman Catholicism, although in some instances it is profoundly modified and influenced through syncretism. A common syncretic religion is Santería, which combined the Yoruba religion of the African slaves with Catholicism and some Native American strands; it shows similarities to Brazilian Umbanda and has been receiving a degree of official support. The Roman Catholic Church estimates that 60 percent of the population is Catholic,[2] but only 5% of that 60% attends mass regularly,[3] while independent sources estimate that as few 1.5% of the population does so.[4] In a survey sponsored by Univision, 44% of Cubans said they were not religious and 9% did not give an answer while only 34% said they were Christian.[5]