Endogamy is the cultural practice of marrying within a specificsocial group,religious denomination,caste, orethnic group, rejecting any from outside of the group or belief structure as unsuitable for marriage or other close personal relationships. Its opposite,exogamy, describes the social norm of marriage outside of the group.
Endogamy is common in many cultures and ethnic groups. Severalreligious andethnic religious groups are traditionally more endogamous, although sometimes mating outside of the group occurs with the added dimension of requiringmarital religious conversion. This permits an exogamous marriage, as the convert, by accepting the partner's religion, becomes accepted within the endogamous group. Endogamy may result in a higher rate ofrecessive gene–linkedgenetic disorders.
Endogamy can encouragesectarianism and serves as a form of self-segregation. For instance, a community resists integration or completely merging with the surrounding population. Minorities can use it to stay ethnically homogeneous over a long time as distinct communities within societies that have other practices and beliefs.
Theisolationist practices of endogamy may lead to a group's extinction, as genetic diseases may develop that can affect an increasing percentage of the population. However, this disease effect would tend to be small unless there is a high degree of close inbreeding, or if the endogamous population becomes very small in size.
TheUrapmin, a small tribe inPapua New Guinea, practice strict endogamy. The Urapmin also have a system of kinship classes known astanum miit. Since the classes are inheritedcognatically, most Urapmin belong to all of the major classes, creating great fluidity and doing little to differentiate individuals.[1]
The small community on theSouth Atlantic island ofTristan da Cunha are, because of their geographical isolation, an almost endogamic society. There are instances of health problems attributed to endogamy on the island, includingglaucoma andasthma as research by theUniversity of Toronto has demonstrated.[2]
Endogamic marriage patterns may increase the frequency of various levels ofcousin marriage in a population, and may cause high probability of children of first, second, third cousins, etcetera.
If a cousin marriage has accrued in a known ancestral tree of a person, in historical time, it is referred to aspedigree collapse. This may cause relations along multiple paths between a person's autosomal-DNA matches. It creates stronger DNA matches between the DNA matches than expected from the nearest path.[3]
Cousin marriage should not be confused withdouble cousins, which do not cause a pedigree collapse. Certain levels ofsibling marriage and cousin marriage is prevented by law in some countries, and referred to asconsanguinity.
A long term pattern of endogamy in a region may increase the risk of repeated cousin marriage during a long period of time, referred to asinbreeding. It may cause additional noise in the DNA autosomal data, giving the impressions that DNA matches with roots in that region are more closely related than they are.
Greek Cypriots usually practice endogamy in order to maintain their status as the majority ethnic group on the island ofCyprus.
Judaism traditionally mandates religious endogamy, requiring that both marriage partners be Jewish, while allowing for marriage to converts.Orthodox Judaism maintains the traditional requirement forendogamy in Judaism as a binding,[15] inherent part of Judaism's religious beliefs and traditions.[16]
TheKnanaya, community claims to have arrived to India in the fourth century and have been noted for their historical practice of endogamy.[citation needed]
Lepcha, an ethnic group in India, Nepal, and Bhutan.[18]
TheSurti and the Kaanam (Bharuchis) ofGujarat. In Gujarat on either side of theNarmada River lie two major cities,Surat andBharuch. Those lying south of Narmada are generally termed as Surtis and those north of it are termed as Kaanam. Endogamy was historically practiced amongst these two groups and it continued as they migrated to other regions of the world. Surtis would only marry Surtis and Kaanams would only marry Kaanams. It is only recently in the past 50 years that this practice has been discontinued. Before that, if a girl's family could not find a suitable partner amongst their group in the migrated land, they would prefer getting her married to a boy from back home (Gujarat) even though boys of marriageable age would be available in their land of migration.
^Robbins, Joel (2004).Becoming Sinners: Christianity and Moral Torment in a Papua New Guinea Society. University of California Press. pp. 191–192.ISBN0-520-23800-1.
^Bonné-Tamir, B.; Korostishevsky, M.; Redd, A. J.; Pel-Or, Y.; Kaplan, M. E.; Hammer, M. F. (March 2003). "Maternal and paternal lineages of the Samaritan isolate: mutation rates and time to most recent common male ancestor".Annals of Human Genetics.67 (Pt 2):153–164.doi:10.1046/j.1469-1809.2003.00024.x.ISSN0003-4800.PMID12675690.