25 Consanguineous Marriages in India

Dr. Rajesh Kumar Gautam

epgp books

 

CONTENTS:

 

Learning outcomes: At the end of the module the reader will know

  • Consanguineous Marriages
  • Reasons of consanguinity
  • Sociodemographic aspects of consanguinity
  • Religious and legal regulation of consanguineous marriage
  • Preferential Consanguineous Union
  • State wise prevalence of consanguineous marriages in India
  • Religion wise prevalence of consanguineous marriages in India
  • Drawback of Consanguineous marriages

 

Introduction

 

Marriage is a universal institution evolved in the course of cultural-evolution. It is a legally and socially sanctioned union between one or more husbands and one or more wives that accords status to their offspring and is regulated by laws, rules, customs, beliefs and attitudes that prescribe the rights and duties of the partners. The universality of marriage within different societies and cultures is attributed to the many basic social and personal functions for which it provides structure, such as procreation, sexual gratification and regulation, care of children and their education and socialization, regulation of lines of descent, division of labour between the sexes, economic production and consumption, and satisfaction of personal needs for affection, status, and companionship.

 

India is a country of diversities, where variety of cultures and people co-exists. Beside bio-ethnic variation, the people are divided into various caste groups. Even, the religious groups like Christianity and Islam have casteism or they are treated as a caste. These castes are endogamous. Beside castes and religious groups, Indian is also inhabited by a large number of tribal groups many of them are in the earliest stage of development and cultural-evolution. Earliest form of cultural institutions like matrilineality and polyandry still exist among Indian tribes (Gautam and Kshatriya 2011, Gautam, Kshatriya and Kapoor, 2007).

 

There are different types and form of marriages based on different criterion. For example: group marriage, polygamy, monogamy, endogamy, exogamy, hypergamy, hypogamy, levirate marriage, sorrorate marriage and so on. Consanguineous marriage is based on kinship.

 

The word consanguineous comes from the two Latin words “con” meaning shared and “sanguis” meaning blood. Consanguinity describes a relationship between two people who share an ancestor, or share blood. Such marriages are favoured by different populations usually bound to traditional customs, beliefs and to keep property in united form within the family.

 

The occurrence of consanguinity in a population depends on various factors viz. population structure, migration, cultural practices and so on. Generally very close consanguineous mating are avoided in human population. Practically, in all human societies incest is considered to be taboo. The degree of relationship at which mating is considered incestuous may differ slightly from one society to another, but, in general, parent-offspring and brother-sister mating are forbidden in all societies. Still, incestuous union may be in most of the societies, but, they are negligible in proportion.

 

All human societies have some incest taboos. These are rules and laws that prohibit marriage or sexual relations, or both, between certain kinds of kin. The kinds of kin always include some consanguineous classes, and one theory of the establishment of incest laws is folk knowledge of undesirable inbreeding effects in offspring of such unions. Incest taboos are not uniform restrictions to a particular grade, however, and often extend to non-consanguineous relations. Other theories of the origin of incest, therefore, include analysis of its effects on stability of the family as an economic and educational unit and ascribe the definition of incest in various societies to social and psychological motives.

 

Consanguineous marriage is practiced by many communities around the world. Literature reports a historically high prevalence among the Middle East countries, North Africa and South Asia accounting for 20-50+% of all marriages. First cousin (F = 0,0625) unions are more frequent comprising 20-30% of all marriages (Bittle and Black, 2010 and Bittle 2010).This social custom is practiced mainly for religious and economic reasons. In some religions marriages between first cousins and uncle-niece is permitted, but not between brothers and sisters. Among the Hindu population of South India, about 30% of marriages are consanguineous, with 20+% between uncle-niece unions (F = 0.125) (Bittle et al. 1991). Marriage of a boy with his mother’s brother’s daughter is opposed. But, uncle-niece unions (but not aunt-nephew) are permitted in Judaism. In Arab Muslim communities, first cousin unions between a man and his father’s brother’s daughter are preferred.

 

India is subdivided into two major regions with respect to a preference for or avoidance of consanguineous marriage, a subject that strongly attracted the attention of J. B. S. Haldane (Haldane 1963). The interest expressed by Haldane was instrumental both in the inclusion of a sub-survey on consanguinity within the 1961Census of India (Roychoudhury 1976) and in numerous subsequent studies into the prevalence of both consanguineous and affinal marriage (Chakravarti 1968; Roychoudhury 1976, 1979; Singh and Tyagi 1987).\

 

Reasons of consanguinity

 

There are several circumstances that would give a population a reason to practice consanguinity at a large scale. Some of these reasons for practicing consanguinity include royalty, religion, rural background, culture, casteism, poverty, isolation and small population size. Among many of Indian tribes cross cousin marriages are considered as preferential marriage.

 

Consanguineous unions are preferred in some communities as it is believed to strengthen family relations. The fear of marrying with stranger, maintenance of family property, requirement of less economic transaction (dowry) and cultural practices favour intra-familial marriages (Bittles, 1994). Marriages within the relatives are also believed to be more stable, have better relationships with in-laws, favors the practice and continuity of cultural practices. Parents believe that in close kin relationships physical traits of the bride will be less important and in-laws will be more caring and supportive (Bittles, 1994). Among the major population studies reported consanguinity is found to be associated with socio-economic levels, education and rural communities.

 

Sociodemographic aspects of consanguinity

 

The specific types of consanguineous marriage that are favoured can vary quite widely between and within different countries, with religious, ethnic, and tribal traditions playing a major role at local and national levels. The reasons most commonly given for the popularity of consanguineous marriage can be summarized as: a strong family tradition of consanguineous unions; the maintenance of family structure and property, and the strengthening of family ties; financial advantages relating to dowry or bridewealth payments; the ease of marital arrangements and a closer relationship between the wife and her in-laws; and greater marriage stability and durability (Bittles 1994). The degree of social compatibility, and the close involvement of the entire family in consanguineous unions, may explain both the greater stability that has been claimed for consanguineous unions, which have lower divorce rates, and enhanced female autonomy. Among the major populations so far studied, the highest rates of consanguineous marriage have been associated with low socioeconomic status, illiteracy, and rural background.

 

In some populations a high prevalence of marital unions between close relatives has however been reported among land-owning families, and in traditional ruling groups and the highest socioeconomic strata (Bittles 1994, 1995a).

 

Religious and legal regulation of consanguineous marriage

 

There appears to be no particular rationale for the subdivision of human populations into opposing forms of marriage preference, and even within the major religions there are quite marked differences in attitude to close kin marriage (Bittles et al. 1999). Thus in Christianity, the Orthodox churches prohibit consanguineous marriage, the Roman Catholic church currently requires Diocesan permission for marriages between first cousins, and the Protestant denominations sanction marriages up to and including first cousin unions.

 

A similar degree of non-uniformity exists in Hinduism. The Aryan Hindus of northern India prohibit marriage between biological kin for approximately seven generations on the male side and five generations on the female side (Kapadia 1958). By comparison, Dravidian Hindus of South India strongly favor marriage between first cousins of the type mother’s brother’s daughter (MBD) and, particularly in the states of Andhra Pradesh, Karnataka and Tamil Nadu, uncle-niece marriages also are widely contracted.

 

In general, Muslim regulations on marriage parallel the Judaic pattern detailed in Leviticus 18: 7-18. However, uncle-niece unions are permitted in Judaism. Yet they are forbidden by the Koran, even though double first cousin marriages, which have the same coefficient of inbreeding (F = 0.125), are recognized within Islam. In southern Asia, Buddhism sanctions marriage between first cousins, whereas the Sikh religion forbids consanguineous marriage, although some minority Sikh groups appear to exercise flexibility in the observance of this proscription.

 

Legislation

 

A similar lack of coherence exists in legislation enacted in different countries to govern permitted types of consanguineous relationships in marriage. For example, first cousin marriages are legal in countries such as the U.K. and Australia, but they are criminal offenses in eight of the states of the U.S.A. and illegal in a further 31 states (Ottenheimer 1990). Yet exceptions can be incorporated into state laws, for example, to permit uncle-niece marriage within the Jewish community of Rhode Island (Bratt 1984).

 

Legislation approved and adopted at the national level may also prove to be inoperable in practice, as exemplified by the Hindu Marriage Act of 1955 which includes a ban on uncle-niece marriage (Kapadia 1958). Yet in a study conducted between 1980 and 1989 in Bangalore and Mysore, the two major cities of the state of Karnataka in southern India, 21.3% of Hindu marriages were uncle-niece unions (Bittles et al. 1992). Consanguineous unions are regarded as customary for the peoples of southern India, i.e. those living south of the Narmada River. Cross-cousin marriage was recognized in the Hindu Marriage Act of

 

1955, and the legality of uncle–niece unions was subsequently confirmed in the Hindu Code Bill of

 

1984 (Appaji Rao et al. 2002).

 

Preferential Consanguineous Uni

 

Most common form of consanguineous marriage in all major societies is between first cousins, the importance of customary influences is apparent from variations in the specific types of first-cousin marriage contracted. While marriage to mother’s brother’s daughter is the strongly preferred form of consanguineous union among Indian Hindus, all four types of first-cousin union, i.e. to father’s brother’s daughter, to father’s sister’s daughter, to mother’s brother’s daughter, and to mother’s sister daughter, are common among different Indian population.

 

State wise prevalence of consanguineous marriages in India

 

India is a multi ethnic, multi-lingual country having wide diversity on the basis of region, religion, caste, culture, custom, believes and so on. In most of the cases, there are arrange marriages. Caste endogamy is also very common. In spite of different forms of marriages, a wide range of population in Indian still practice consanguinity or consanguineous marriages.

 

As per National Family Health Survey 1992-93 (IIPS 1995) south of India has higher prevalence of consanguineous marriages. Andhra Pradesh and Karnataka have highest prevalence (30%) of such marriages; followed by Maharashtra (21%) and Goa (10.6%). Kerala and Uttar Pradesh have almost similar prevalence of consanguineous marriages i.e. 7.5%. In northern India the highest prevalence of consanguineous marriages are in the state of Jammu and Kashmir (8%) followed by Uttar Pradesh. The lowest prevalence of such marriages were reported from the state of Punjab, Haryana and Himachal Pradesh i.e. nearly 1%. The capital of India i.e. Delhi have 4.3% consanguineous marriages. In central India, the prevalence varies from 4.1 to 7.5%. In east India the prevalence is 5 to 5.7%. In general, the prevalence of consanguineous marriages is low in North-East India. The state of Arunachal Pradesh have 3.9% of such marriages, which is highest in North-East and Mizoram have lowest (0.5%) consanguineous marriages

 

Table 2: Consanguineous marriages among different Indian population (After Bittle 1998).

 

For further elucidation of state wise consanguineous marriages and mean coefficient of inbreeding (F) the data are presented in Table 1 and Figure 1. The all India average of consanguineous marriages was 11.9%. In different sporadic studies around the country during 1961 to 1993 the prevalence of consanguineous marriages varies from 0.5% to 46% (Table 2)

 

Table 3. Consanguineous marriages in India by Religion, 1992-1993 (After Bittles 2002).

Figure 3. Religion wise prevalence of consanguineous marriages in India.

 

Consanguineous marriages by religion in India are presented in Table 3 and Figure 3. It is apparent that the Muslims have higher prevalence (31%) of consanguineous marriages followed by Buddhist 22%. Hindu and Christian have similar prevalence of such marriages i.e. 14%. Jain and Sikh have 6% and 2% consanguineous marriages respectively.

 

Drawback of Consanguineous marriages

 

Many different types of genetic disorders have been reported to be more common among consanguineous progeny, for example congenital disorders (Centerwall and Centerwall 1966; Asha Bai et al. 1981; Agarwal et al. 1991), including neural tube defects (Kulkarni et al. 1989; Jain et al. 1993) and congenital heart defects (Jain et al. 1993; Badaruddoza et al. 1994; Gnanalingham et al. 1999). Autosomal recessive hearing loss disorders (Chen et al. 1997) and visual defects such as early-onset retinal dystrophies (Rahi et al. 1995), primary congenital glaucoma (Panicker et al. 2002) and anophthalmos (Hornby et al. 2001) also are present at increased prevalence. The excess risk that an autosomal recessive disorder will be expressed in the progeny of a consanguineous union is inversely proportional to the frequency of the disease allele in the gene pool (Bittles 2001). For this reason, during the last decade many disease genes that are rare in the general population have been identified and their chromosomal locations mapped by studying highly inbred families with multiple affected members.

 

A study has provided the evidence for inbreeding depression on cognitive abilities among children, with high frequency of mental retardation among offspring in proportion to their increasing inbreeding coefficients (Fareed and Afzal, 2014a). The depression on growth parameters (height, weight and body mass index) due to inbreeding among children has revealed the significant increase in underweight cases with increasing inbreeding coefficients (Fareed and Afzal, 2014b).

 

Primary infertility appeared to be reduced and there was little general evidence of increased numbers of miscarriages or stillbirths among consanguineous union (Bittles 2001). Thus a meta-analysis conducted on 30 populations showed that at levels of consanguinity from F = 0.0156 to F = 0.125 the mean number of live births was higher in consanguineous than nonconsanguineous unions, and for first-cousin marriages (F = 0.0625) the fertility

 

Differential was significant at P < 0.0001 (Bittles et al. 2002). Most studies in India have indicated that early postnatal mortality is higher in the progeny of consanguineous unions, owing to the expression of deleterious recessive genes. Consanguinity-associated deaths are largely concentrated during the first year of life (Hussain et al. 2001), and multiple deaths have been reported in specific consanguineous families in proportion to the level of parental genetic relatedness (Bittles et al. 1991). The mean coefficient of inbreeding for the total population of India in the 1992–1993 National Family and Health Survey (IIPS 1995) was a =    0.0075 (table 1). The data of Bittles and Neel (1994), where consanguinity associated mortality to approximately 10 years of age averaged 44/1000 births at F = 0.0625, would suggest that on a national basis consanguinity would be a contributory factor in 5.2/1000 deaths (Bittles 2002).

 

A recessive gene carried in a single dose in a common ancestor may remain hidden until it comes to light for the first time in an inbred descendant. Therefore, recessive traits will occur with increased frequency in the progeny of consanguineous mates

 

Conclusion

 

It is established that increased urbanization and the gradual shift to smaller family sizes will impose constraints on consanguineous marriage in future generations. In this respect, a reduced prevalence of uncle–niece marriages would appear to be especially likely because of unacceptable age differentials between the potential partners (Radha Rama Devi et al. 1982). It seems probable that this decline will not be uniform in effect across populations but will be mainly observed in urbanized populations and among couples who share higher educational standards and later ages at marriage. The specific type of consanguineous union contracted may also prove to be an important determining factor.

 

As family sizes reduce, double first cousin and uncle-niece marriages in particular will become increasingly difficult to arrange within the accepted norms of spousal age difference at marriage. At the same time, there may be lesser emphasis placed on the requirement to marry within the prescribed consanguineous marriage pattern, for example, mother’s brother’s daughter in southern India, in order to ensure that a marriage within the family can be contracted. At the same time it should be noticed that in the Muslim population of India there has been no evidence of a reduction in consanguineous marriage during the last 40 years (Hussain and Bittles 2000).

 

With improving socioeconomic conditions, the incidence of primarily “environmental” disease is declining in most developing countries owing to better basic public health measures and the introduction of vaccination programs for lethal childhood infectious diseases. As a result, genetic disorders now account for an increasing proportion of morbidity and death. This epidemiological transition has already been observed over the course of the last two generations in more developed, low mortality countries, and within the last two decades it also has become evident in the Gulf States, where favorable socioeconomic circumstances have been translated into advanced diagnostic and health care facilities.

 

Our limited knowledge and understanding of consanguinity is unfortunate, especially since in Western societies the information that is available tends to be overly focused on the undesirable clinical outcomes of close kin marriage, which adversely affect a minority of families and individuals. This lack of balance operates to the detriment of the much larger proportion of consanguineous couples whose children do not show identifiable deleterious biological effects, and to whom the social and economic benefits of a consanguineous union appear obvious.

 

Given the numbers of consanguineous marriages contracted in the world’s most populous country like India, and the fact that inherited disorders which currently are lethal in less developed societies, it is essential that multidisciplinary surveys should be conducted to estimate the extent of the problem, accompanied by the initiation of community-based counseling programs and lifetime care under improved treatment facilities. Programs of this nature would clearly be beneficial to human society as a whole.

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