Science & Lifestyle: Pros and Cons of Cousin Marriage

What is your take on marrying a close cousin? Are you falling in love with a cousin? Here is all you need to see first.

Hispanic family happily enjoying the moment together
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While individuals and groups still align on opposite sides of the idea of close-cousin marriage, the majority of the world is against it. But here, we will explore the pros and cons of cousin marriage using facts based on science and societal life.

Marriage to a close cousin is known as “consanguineous marriage” and is referred to as a marriage between two people related as second cousins or closer.

Oftentimes, people get romantically attracted to their close cousins and may want to take it a step ahead to marry them. And while many cultures and traditions have vehemently resisted the idea of close-cousin marriage, some people have decided to push everything aside to pursue love with the one they love irrespective of what society thinks.

However, there are some things you need to know before you go ahead with this practice of consanguineous marriage. Whatever the strongest point is, you just need to keep an open mind to embrace it, even if it means having to take a decision you or your family do not fully agree with.

Brief Historical Perspective of Consanguineous Marriage

Close-cousin marriage was encouraged and practised by some indigenous cultures in Australia, North America, South America, and Polynesia many years ago. Today, with increasing civilization, many of these practices have been abolished.

Historically, some form of Hinduism and Catholicism strictly prohibits cousin marriage while others like Protestantism, Islam and Judaism support cousin marriage between even as close as first cousins.

Since the 19th century, close-cousin marriage has been on the decline globally. However, some parts of the Middle East and South Asia still strongly allow close cousins to marry. Under Australian law, you can marry a cousin, niece, nephew, aunt, or even an uncle.

In Africa, cousin marriage is allowed between cousins whose family connection have been considerably distant, say 5th or 6th cousins apart. They link cousin marriage to superstition, saying that there is an ancestral curse on those who marry their cousins even if they ignorantly did so. Usually, for such cousins who marry anyway, they require certain traditional rites to be performed to lift off the curse before they proceed, otherwise, they may purportedly face grievous consequences.

Another related entity to close cousin marriage in the African setting is incest. Many parts of Africa frown at sexual relationships between cousins or close relatives. But most of these are based on unknown reasons and superstition, requiring us to find more concrete reasons for or against consanguineous marriage as we will see shortly.

Pros of Close Cousin Marriage

Some notable people who were cousins and got married to each other include:

  • Charles Darwin and his wife, Emma (first cousins)
  • Saddam Hussein and Sajida Talfah (first cousins)
  • Albert Einstein and Elsa Lowenthal (first cousins on mother’s side and second cousins on father’s side)
  • Franklin D Roosevelt and Eleanor
  • Thomas Jefferson and Martha Wayles Skelton (third cousins)

They did experience bliss in their marriage, but what other benefits could they have had in deciding to marry a cousin?

The major benefits of consanguineous or close cousin marriage in most societies which practice it include the preservation of cultural values and family wealth, maintenance of physical closeness between relatives and strengthening of family ties between a wife and her relative in-laws.

These benefits are worthwhile, especially in cases where there is a need to ‘sustain a royalty bloodline’, protecting a tradition from extinction.

Other benefits of consanguineous marriage include:

  1. Strengthening of the inheritance pool until a stable uniform gene pool is achieved.
  2. Sustaining of ‘royal blood’ in cases of royalties and monarchy.
  3. Science has shown that children born in cousin marriages have a slightly lower birth weight, thus preventing fetal macrosomia and its complications.
  4. It is easier for couples to adapt to their new life together as the family cultures are much more similar compared to non-consanguineous unions.
  5. Due to the recirculation of ‘pure genes’, newborns from a cousin/consanguineous marriage have been observed to have higher growth and thriving potential than others.

Now that we have seen some benefits of close-cousin marriage, it is time to weigh them against the cons as you will see in the next section.

Cons of Close Cousin Marriage

The major cons of close-cousin marriage revolve around risks of genetically acquired diseases and lack of social integration with other groups of people and families.

These are as follows:

1. Increased Risk of Genetic Diseases and Birth Defects

Certain chromosomal, genetic and congenital anomalies can run in a family, whatever their background or ethnicity. However, some of these anomalies may remain recessive in the absence of a second copy of the genetic component.

Being married to a cousin significantly increases the risk for congenital defects and chromosomal anomalies by making available a second copy of a defective gene or gene pair. This is known as recessive transmission where one out of two gene defects is not enough to manifest as a disease.

For example, Tay-Sachs disease which is a recessive genetic disease is common among the Ashkenazi Jews. That means marriage and childbearing between two Jews or close cousins who have only one Tay-Sachs gene increases the likelihood of producing children with both gene pairs which can manifest as a disease.

Other common recessive genetic diseases that could be related to consanguinity include cystic fibrosis and sickle cell disease.

The Lancet has also shown that the risks of birth defects are higher in close cousin marriages than in distant unions.[1]Cousin Marriage and Genetic Inheritance Leaflet.pdf (Bradford.gov.uk)

2. Lack of Social Unity and Ethnic Diversity

Social unity and ethnic diversity are exemplified by people’s openness to have relations with other people outside their culture, race, or ethnicity. It shows the extent of universal acceptance we have attained.

We are the modern man – Homo Sapiens – and we all share the same genes and capabilities. We are all reproductively compatible, that is, we can reproduce viable children together. But for some reason, we are still closed up to the idea of “mixing up” with our other brothers out there.

Universal ethnic inclusion has so many advantages, including the creation of newer genetic variations of our gene pool that will be more adaptable to differing cultures and geography, the bridging of language and food barriers, and the restoration of global peace and harmony, among other benefits.

3. Poor Political Relationships

The Royal Marriages Act 1772 of the Parliament of Great Britain prescribed the conditions for which a British royal could contract a valid marriage to preserve the monarchical status of the royal house. In this prescription, before any royal marriage is conducted, it must first meet the minimum criteria for acceptance by the parliament, either lawfully or out of special consideration.

The laws are stringent but they sometimes allow marriage between royals and deserving commoners. Otherwise, who knows if Prince Harry would have been allowed to marry Meghan Markle?

Just like social unity and ethnic diversity I talked about above, rules like this, especially if held more stringently, can cause some form of political restrictions. How do you imagine the level of peace and harmony that would exist if America and China were marital in-laws, literarily?

For example, if only princes were allowed to marry princesses, and vice-versa, with time they would all become cousins of each other. This can politically restrict them from mingling with other big kingdoms out there and miss out on that wonderful opportunity to gain more political influence beyond their shores.

The Caveats of Consanguineous Marriage

Now that you have seen the pros and cons of close-cousin marriages, you might be wondering if you could still marry your cousin or not. Here is the caveat.

From the standpoint of creation and evolution, we are all cousins genetically. The only difference is that we are genetically distant. That means we are already marrying our cousins unknowingly and acceptably.

However, a marriage is said to be consanguineous if it is between two close cousins one to two generations apart. That is to say, the farther apart we get, the more acceptable it is to co-marriage. I also think this is nature’s way to bring us all together.

While one of the major problems of close cousin marriages is that of birth defects and genetic diseases, this would soon be a matter of the past as it can be solved via modern genetic testing tools available today. However, it is naturally more feasible to not marry close cousins in the process of consanguinity.

I am a medical doctor, a seasoned writer and passionate blogger. Thanks to many years of trials, failure, and near successes. I am the founder of Knowseeker and our content are geared towards enlightening and making you a better and happier audience.

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