The frequency of consanguineous marriages varies from one population to
another. Consanguineous marriage is not restricted to specific religions or to population
isolates, but is a long-standing practice in many regions of the world and it continues to
be preferred by many populations, with more than 1,000 million people living in
countries where between 20% and 50+% of marriages are consanguineous. Levels
above 5% occur in the northern part of Africa, the Middle East and parts of Asia,
whereas in what is described as the "Western world" – i.e. the entire North American
continent, the whole of Europe (with the exception of Spain), Australia and New
Zealand – the frequency is less than 1%. In South America, parts of eastern and southeast
Asia, Spain and various parts of Africa the rate is between 1 and 10%. In other
parts of the world the frequencies are unknown.
Keywords: Africa, consanguineous marriages, frequency, Middle East,
populations.