The Middle East has particularly high rates of cousin marriages among regions of the world. In one study, Iraq was estimated at a rate of 33% for cousins who marry. Since the 13th century, the Catholic Church has measured inbreeding according to the so-called civil law method. In this method, the degree of relationship between the straight-line parents (i.e. a man and his grandfather) is simply equal to the number of generations between them. However, the degree of relationship between collateral (non-linear) relatives is equal to the number of links in the family tree from one person to the common ancestor and then back to the other person. Thus, brothers in the second degree are related and cousins of the first degree in the fourth degree.  In Pakistan, marriage between cousins is legal and customary. The reasons for inbreeding are economic, religious and cultural.  Data collected in 2014 from Malakand district of Khyber Pakhtunkhwa province (KPK) in Pakistan showed that about 66.4 percent of marriages among rural couples were with a first cousin or a second cousin.
   In some areas, it has been found that a higher proportion of first-degree marriages in Pakistan is the cause of an increased rate of blood disorders in the population.  Global map showing the prevalence of marriages between second-degree cousins and second-degree cousins according to data published in 2012 by the US National Center for Biotechnology Information.  A bill to lift the ban on marriage to first cousins in Minnesota was introduced by Phyllis Kahn in 2003, but died on the Order Paper in committee. Republican Minority Leader Marty Seifert criticized the bill in response, saying it would “turn us into a cold Arkansas.”  According to The Wake of the University of Minnesota, Kahn knew the law was unlikely to pass, but introduced it anyway to draw attention to the problem. She came up with the idea after learning that marriage between cousins is an acceptable form of marriage among certain cultural groups with a strong presence in Minnesota, namely the Hmong and Somali.  The Hindu Marriage Act prohibits marriage for five generations on the paternal side and three generations on the maternal side, but allows marriage between cousins when custom permits.   Taiwan and North Korea also prohibit marriage to first cousins.   According to another view, William Saletan of the journal Slate accuses the authors of this study of suffering from the “innate liberal vanity that science solves all moral questions.” Saletan readily acknowledges that the ban on marriage between cousins cannot be justified on genetic grounds, but rhetorically asks whether it would be acceptable to legalize uncle-niece marriage or “pure incest” between siblings, and then let genetic testing deal with the resulting problems.  An article by Sarah Kershaw in the New York Times documents the fear that many married cousins are treated with derision and contempt. “While many people have a story about a secret cousin who had a crush or kissed, most Americans find the idea of cousins getting married and having children disturbing or even disgusting,” the article states. There is the example of a mother, Mrs. Spring, whose daughter Kimberly Spring-Winters, 29, married her cousin Shane Winters, 37.
She explained that when she told people about her daughter`s wedding, they were shocked and she was afraid to mention it. They live in a small town in Pennsylvania and she fears her grandchildren will be treated as outcasts and ridiculed because of their parental status. Another pair of cousins said their children`s maternal grandparents never met their two grandchildren because the grandparents broke off contact by disapproving of the couple`s marriage. This couple did not publish their names.  The Qur`an does not say that marriages between first cousins are prohibited. In Surah An-Nisa (4:22-24), Allah mentions women who are forbidden to marry: To quote the Qur`an: “. You are all allowed beyond those mentioned, so that you can seek them with your wealth in an honest marriage… In Surah Al-Ahzab (33:50), Levi-Strauss postulated that marriage between cousins has the two consequences of establishing classes that automatically delimit the group of possible spouses and determining a relationship that may decide whether to want or exclude a potential spouse.