Karen was right about Seth…

We all remember the scene from Mean Girls when Karen tries to convince her friends that it’s totally normal to like her first cousin, Seth. For those of you who don’t remember the scene, it’s time to brush up on the only movie that matters. Karen, the stereotypical “dumb-blonde” in the movie, spots her cousin at a Halloween party and tells her best friends that she has the hots for him.

The girls look at her in disgust and say “ew that’s your cousin.” Society tells us that our cousins are off limits for marriage, but a recent study suggests that Karen is in the clear. We can marry our parent’s siblings children. It looks like Karen really does have a “fifth sense.”

When and why people stopped marrying their cousins

A study published In the journal, Science, reveals that from the years 1650- 1850 people would marry, on average, their fourth cousins. In the century that followed, the number of cities grew, technology advanced and people started moving out of their neighborhoods. At this point, around 1950, people began marrying their 7th cousins on average.

Bigger sea = more fish

Transportation played an essential role in the change of this marriage trend. It allowed people to travel further than they ever have before. People were exposed to a larger population and traveled to find a spouse. The expression, “there’s more fish in the sea,” started making a lot more sense. If Bob from Sunday school dumped you, you didn’t have to consider dating his friend. You could skip town and move on. Before advancements in transportation, people only traveled in a six-mile radius from where they were born.

Other factors such as changed social norms, increased autonomy in women and smaller families also contributed to the decrease in the number of people marrying their cousins. Back then families were much bigger. Marrying your cousin was convenient and kept the money within the family. The fact that large families lived side by side made it more likely to be related to someone that you know. Once all these things changed, so did the way we look at our family.

After the Civil war, American States began to declare marriage between cousins illegal.

Getting into the genes of it all

First cousins share 12.5% of their genetic makeup, DNA. The further away your relation is to your cousin, the less DNA you share. The issue with sharing genes is that it increases the chances that your offspring are born with diseases. The more dissimilar your genes are to your spouse, the better off your kids are when it comes to health.

Research on the topic revealed that the children of 1st cousins have about a four to seven percent chance of having a birth defect. Children from distant cousins have a lower chance of getting a birth defect. These chances are around three to four percent.

Go for it Karen

Scientists say that these chances of developing a birth defect from two first cousins, and two distant cousins are pretty similar. Therefore, having a child with your first cousin is not high-risk.

There would, however, be an issue if children of those marriages end up marrying each other. So let’s say Karen and Seth are first cousins and have a child, Susan. Susan needs to stay away from any romance with her first cousins because she shares a dangerous amount of DNA with them. Sorry, Susan..

Although the science says its ok, marrying a first cousin is still taboo. The state of Texas and Oklahoma declares marriage between cousins to be a criminal offense. This law may be a love killer, but it also may be a useful precaution. Susan might develop romantic feelings towards her first cousins. Afterall, her parents are madly in love. It’s these types of thought processes that get us in trouble.

However, California and New York deem it legal to marry a first cousin. Hopefully, the children resulting from these marriages need to know that their first cousins are off limits. Otherwise, we would have a big problem.

Famous people who married their cousin

Some of the most famous people married their cousins. Albert Einstein, Eleanor and Franklin Roosevelt, Edgar Allan Poe, Thomas Jefferson, Kevin Bacon and even CHARLES DARWIN!