Hinduism Perspective on Cousin Marriage
While many may assume that Hinduism, like many other Eastern Religions, allows for cousin marriage, this is only half true. Hindus are divided into two separate and opposing schools of thought regarding cousin marriage.
The Dravidian Hindus of South India find marriage between cross-first cousins (the related parents of each cousin being a brother and sister) to be a preferred marital union. (Bittles book).
In contrast, the Aryan Hindus of North India strongly oppose consanguineal marriages within seven generations on the male side, and five generations on the female side of the family. (Kapadia 1958)
According to the Hindu Marriage Act of 1955, the degrees of prohibited relationships in marriage includes first cousins, as well as marriages between an uncle and niece. This prohibition extends to those who are related by half or full blood, and adoption. Interestingly enough, the law also specifies that those who are illegitimately related, (resulting from non-marital affair) are included in the prohibition. One would routinely assume that since an illegitimate relative still carried the same genetic similarity as a relative born legally into the same family, that this would not need to be specifically addressed.
Even so, the law seems to go unenforced among the Dravidian Hindus. A study conducted from 1980 to 1989 in two major South Indian cities reflected that 21.3% of Hindu marriages were consanguineous. (Bittles, Shami and Appaji Rao 1992).