There’s Your Twin Somewhere in the World Right Now and We’ll Prove It to You
"I was the last person to board the plane and I saw that someone was already in my seat, so I asked him to move. He turned to me and I saw my own face in front of me... All the people on the plane were looking at us and laughing."
This is the recollection of Neil Douglas, who was flying to Ireland for an ordinary wedding on a regular day. He found himself in the unusual situation where he met his own twin. Not only had the stranger twins accidentally bought plane tickets for similar seats, but they also met in a hotel later, and then in a bar (well, okay, the bar was planned).
And now just imagine that the same thing could happen to any individual in the world! You might have heard the legend that nature creates 8 identical people and puts them in different places across the world, so that at least one of them survives. And if they meet, the system fails and one of the twins dies.
We at Bright Side don't believe these tales, but we can prove right not that, in theory, you really might have a twin.
1. Only 0.1% of the genome is responsible for a person's uniqueness
The first point here is based on the fact that 99.9% of the genome in the entire human race is absolutely identical, and only 0.1% is responsible for our uniqueness. And there are even fewer genes which determine our appearance itself. So, despite the sheer number of possible DNA combinations, identical appearances don't seem unbelievable in theory. This could be the explanation why there are so many rumors about famous people having twins.
Of course, a full match of even this small percentage can happen only in one out of a billion cases, as with "the infinite monkey problem": sit a monkey in front of a typewriter for long enough and eventually it will surely write the Complete Works of William Shakespeare by randomly hitting the keys on the keyboard.
Ignoring grammar, the monkey has a one in 26 chance of correctly typing the first letter of Macbeth. So far, so good. But already by the second letter, the chance has decreased to one in 676 (26 x 26) and by the end of the fourth line (22 letters), it’s one in 13 quintillions. When you multiply probabilities together, the chances of something actually happening disappear very, very quickly.
But still, there is a chance!
This is why, theoretically speaking, out of 7 billion people, there could be one person whose DNA matches yours to a pretty significant extent. For example, take a look at this amazing story by Valeriy Panushkin about bone marrow donors:
2. You might turn out to be distant (very distant) relatives
And here's the second rationale: if you look at this question not from the point of view of genetics, but from that of mathematics, then unknown twins could simply be relatives. According to calculations, a person can have more than 250 relatives after approximately 8 generations, and within 30 generations, the number of relatives can be higher than 1 million. So, it's no wonder that you could potentially meet your distant cousin who has the same appearance as you.
For example, while we were preparing this article, we used the photo project of Francois Brunelle, which has helped to bring together many Canadians who were separated in childhood. Who knows, maybe they're just relatives?
The only hope we have is that in the future, the faces of all the 7 billion people who live in the world will be in some kind of a database (like this website) — then we'll be able to talk about looking for our twins. So far, such encounters have been miracles, unless your twin plays in some cute Hungarian movie or makes some trash art film with his phone.