6 Countries with the Highest % of Consanguineous Marriages United Arab Emirates Data on consanguineous marriage is often spotty and incomplete. Rates shown should be viewed as best available estimates rather than precise statistical data. 2023 data released by the Turkish Statistical Institute indicated that consanguinuity among first cousins had fallen from 5.9% of marriages in 2010 to 3.2% in 2023. These data exclude other forms of consanguinuity, such as marriages between more distant cousins, siblings, half-siblings, uncles and nieces, and so on, but could signal a larger trend that consanguinuity as a whole is on the decline. The coefficient of inbreeding for a child of a consanguineous marriage is the probability that the child’s DNA includes two alleles at a given locus that are both from the same common ancestor of the two parents (for example, first cousins likely share a common grandparent) and are thus identical by descent (autozygous). A higher coefficient of inbreeding indicates a greater degree of consanguinity (inbred-ness) and a higher likelihood that the child will have recessive genetic disorders compared to the general population. Consanguineous marriage rates have decreased significantly in Bahrain in recent decades. A study published by Cambridge University Press in 2011 determined that the rate of consanguineous marriages had dropped from 39.4% in 1990 to 10.4% (6.8% among first cousins + 4.6% among more distant cousins) in 2009. Sudan and South Sudan were measured together. It has been suggested that South Sudan’s rate of consanguinuity would differ (due to differing cultural norms) if measured separately from Sudan, but authoritative data on the topic was not yet available as of July 2026. Inbreeding refers to situations in which individuals who are closely related to one another (such as siblings or cousins) procreate and produce offspring. Inbreeding can occur among humans as well as animals. Inbreeding is uncommon in most developed countries, but contributes a statistically relevant portion of the total number of births in certain developing countries . The practice of marriages between close relatives (typically cousins) is known as consanguineous marriage. Although rare in the Americas and modern Europe, consanguineous marriage is notably common in North Africa and the Middle East, where it is a traditional and respected aspect of many Arab and Muslim cultures. In many countries, consanguineous marriages and inbreeding are considered illegal. Sexual relations between consanguineous couples is typically referred to as incest in these regions. What Country has the Highest Rate of Inbreeding in the World? Although precise per-country data is rare, it is widely accepted that countries in the Middle East, North Africa, and parts of Western Asia have the highest rates of inbreeding in the world. Countries with traditionally high rates of consanguineous marriage and inbreeding include Pakistan, Saudi Arabia, Lebanon, Egypt, and Israel. What Segments of the Human Population are known for Inbreeding? A certain degree of inbreeding can be difficult to avoid in isolated or cloistered societies, such as the populations of small islands or ethnic/cultural groups such as immigrants or Amish, where the range of possible marriage partners is limited. These conditions can artificially limit potential mates for members of the population, driving up rates of inbreeding. For example, members of the Amish community may have higher rates of inbreeding because they tend to marry other Amish people, which shrinks the size of the population. Members of the Mennonite population may also have higher rates of inbreeding for the same reason. Finally, there are some genetic disorders that are more common among Hasidic and Haredi Jewish groups because they tend to marry members of the same population as well. Medical Concerns Arising from Inbreeding Inbreeding among humans has been proven to increase the risk of certain types of genetic diseases and disorders among certain pockets of the population. Due to the rates of inbreeding in these countries, genetic disorders such as hydrocephalus, neural tube defects, and congenital heart defects are more common. In Palestine and Lebanon, there are also very high rates of children born with cleft lips and palates. However, limited inbreeding in the animal population, particularly when combined with similar-but-healthier methods such as crossbreeding, can be used to increase the prevalence of a favorable trait in that species’ population.

What Qualifies as Inbreeding? In general, mating between individuals who are closer than second cousins is considered inbreeding. As such, relationships between siblings, half-siblings, father and daughter, mother and son, uncles or aunts with their nieces and nephews, and grandparents and grandchildren are considered inbreeding. In many cultures, unions between first cousins are also considered inbreeding, and in some cultures the taboo extends all the way to seventh cousins. Although relationships between people who are second cousins may also be viewed unfavorably by a given society, they are generally not close enough to be considered inbreeding in a biological or genetic sense. Consanguinity and reproductive health among Arabs - National Library of Medicine Table 1 Consanguinity rates in Arab populations - Reproductive Health Journal Inbreeding - Wiki A comparison of inbreeding rates in India, Japan, Europe and China - PubMed Inbreeding and diseases: demographic, genetic, and epidemiologic perspectives - PubMed Inbreeding Levels in Different Countries - Social Biology Measurement of inbreeding from the frequency of marriages between persons of the same surname - Social Biology Consanguinity - Wiki Cousin marriage in the Middle East - Wiki Cousin Marriage - Wiki Consanguineous marriages - National Library of Medicine Global prevalence of consanguinity - Wiki Number of marriages, number of marriages between first cousins and proportion of them by provinces - Turkish Statistical Institute The changing profile of consanguinity rates in Bahrain, 1990-2009 - Cambridge University Press Other Categories