Do you belong to the group of people who have blue eyes? If you do, lucky you! And, are you dating someone that has blue eyes as well? If you do, you are even luckier! You may think that the color of the eyes similarity is no different than dating someone with a similar hair color or skin tone.
According to the revelations of the science, all people that have blue eyes are genetically linked.
So, this means that you and your blue – eyed honey are both related in some way. And what is even weirder, your shared relative can also be narrowed down to one ancestor.
There was a study at the University of Copenhagen which found that blue eyes are actually genetic mutation. Before said mutation, everyone in the world had brown eyes and everyone who has blue eyes is somehow related.
Around 800 people with blue eyes were recruited and it has been found that 99.5% of them had the same mutation in the gene which affects the color of their eyes.
But how is this possible? Well, you should put on your biology caps, as the answer is super simple: it is because of genetic mutations. And these genetic mutations are also the reason why parents with blue eyes wonder how they children have brown eyes.
There was a video released recently by Buzzfeed. It is shown in details how this is possible, by breaking down the science behind genetics.
There are two major genes which are responsible for the color of the eyes: HERC2 (HECT and RLD domain containing E3 ubiquitin protein ligase 2) and OCA2 (oculocutaneous albinism II). The OCA2 gene is activated by HERC2 and the OCA2 also activates proteins which act as pigments. When a mutation appears in either gene, the chain is than broken and OCA2 will not produce pigments, in that way resulting in blue eyes.
How is it possible the children to have brown eyes when both their parents have blue eyes?
There are two genes which every one of us inherits from our parents – one from our dad and one from our mom. When the father has one mutated gene, as well as one working OCA2 gene, the child will still have brown eyes, as they will inherit the dominant gene: the brown eyes.
But, let’s say that both of the parents have mutated gene. In such cases, there is a 25% chance that the baby will have blue eyes. This gene can also be passed down through generations, as it is a submissive gene. This is the same concept as Punnettsquares which you have learned in biology in middle school.
Science is still not totally sure who the relative is that people with blue eyes share. However, the oldest remains of a person with blue eyes was found in Spain. The man is about 7,000 years old and he had a combination of African and European genes. This means that different eye colors appeared in humans before the different skin tones.
After all, your dad is not the mailman. But the bad news is that if you and your loved person both have blue eyes, it means that you are distant relatives.