Until recently, blue eyes have been considered a rare trait among black people. However, researchers have found that some blacks do have blue eyes naturally, thanks to a genetic mutation.
The OCA2 gene is responsible for eye color. It was discovered in 800 people from varying countries, from fair-skinned blond-haired Scandinavians to dark-skinned, blue-eyed people living in Turkey and Jordan.
The Origin of Blue Eyes
Blue eyes are a fairly rare occurrence, with an estimated 8% to 10% of people worldwide having them. Most of these people are of European descent, though black people can also have blue eyes if they inherited the allele from a distant ancestor.
The reason that black people can have blue eyes is because they carry a specific mutation in their DNA that causes them to produce a lower concentration of melanin, which makes their eyes appear blue. This mutation is very different from the other genetic variations that cause green, brown, and gray eyes.
A study published in Nature by Professor Hans Eiberg and his team from the University of Copenhagen found that all people with blue eyes share a single gene mutation. This mutation occurred tens of thousands of years ago around South-Eastern Europe, and is the source of all blue eyes on earth today.
This genetic mutation is very close to the OCA2 gene, which is responsible for melanin production in our bodies and iris (the part of our eyes that contains pigment). The mutation changes how much melanin is produced. This results in a low melanin concentration, which makes the iris blue instead of brown.
Although many people believe that blue eyes only occur in Europeans, they can also be found in Asians and Africans. The allele for blue eyes is recessive, which means that it will only appear in a person if they have both parents carrying the mutation.
According to this study, a majority of blue-eyed individuals share a single mutation in the OCA2 gene, which is the source of their unique eye color. In contrast, some people with blue eyes have health conditions like ocular albinism or Waardenburg syndrome, which can affect a number of other genes and cause their eyes to be light blue instead of dark brown.
This genetic’switch’ that the researchers describe works to inhibit melanin production, but does not completely shut it off, as it can be turned back on later in life if a person has a high-quality OCA2 gene. The results of this research are exciting because it means that we can track the origin of blue eyes, which is an intriguing topic in science.
The OCA2 Gene
The OCA2 gene is a gene that controls the production of melanin, which gives skin, hair, and eyes their color. If someone has a mutation in the OCA2 gene, they have a reduced amount of melanin in their body and their eyes turn blue.
Researchers at the University of Copenhagen found that this mutation is present in 97 percent of people with blue eyes around the world, according to an article published in Science Daily. Geneticist Hans Eiberg and his team studied mitochondrial DNA in people who have blue eyes from countries including Jordan and Denmark.
They used this information to pinpoint the exact site of the gene mutation, which is called an intragenic deletion. Once they located it, the scientists could then compare the mitochondrial DNA of these people to a sample of the same group of people with brown eyes.
This analysis helped the team confirm that the OCA2 gene was the culprit behind the development of blue eyes. They also discovered that the mutation was not present in people with white or light-colored eyes, but only those who have blue eyes.
It turns out that this gene is responsible for the production of melanin in the iris of the eye. If it were inhibited, the pigment would not be produced at all.
However, the researchers found that the mutation doesn’t completely prevent the production of melanin. Instead, it just reduces the amount of melanin that is produced in the iris of the eye. The result is a dilute amount of melanin in the iris and, when combined with light exposure, it produces the appearance of blue eyes.
Several studies have identified variants upstream of the OCA2 gene that are associated with eye color, although it is not clear how they affect melanin production in the iris of the eye. One SNP in this region, rs12913832, is a near perfect predictor of eye color. It also has strong associations with melanoma risk (Branicki et al., 2009; Cook et al., 2009; J Han et al., 2008). Other sites have been reported to be associated with eye pigmentation, and some have a strong association with melanoma risk (Duffy et al., 2007; Sturm et al., 2008; Kayser et al., 2008).
Changing Your Eye Color
There are many ways to modify your eye color, from wearing tinted contact lenses to undergoing a laser procedure. These methods can all be very risky, but if you decide to try them, it is important to get your eyes checked by a licensed optician.
If you have a medical condition that can affect your eye color, such as Fuch’s heterochromia, pigmentary glaucoma, or Horner’s syndrome, you should see an eye doctor before trying to change your eye color. They can determine if the changes are normal or caused by other health problems.
Your eye color is determined by melanocytes in the iris, which secrete the protein melanin. When melanocytes respond to light, they increase melanin production. This causes the iris to turn brown, blue, or green.
It is also possible to alter your eye color with diet. Raw food detox and vegan diets, for instance, can significantly change your eye color.
These diets contain high amounts of antioxidants and glutathione, which can reduce melanin synthesis in the iris. The results can be extremely dramatic and surprisingly natural.
A new surgical technique that can permanently change your eye color has gained traction in the United States. However, it is not available in all countries and the risks are still being investigated.
Most people naturally have brown, blue, or hazel eyes by the time they reach adulthood. This natural coloring can change in the course of puberty or as a result of hormones.
There are other factors that can affect your eye color, including sun exposure and the number of chromosomes in your genes. If you have darker skin, your eyes are more likely to turn brown or blue, and this can be affected by the amount of sunlight that you are exposed to.
Some urban legends say that honey and tepid water can change your eye color. While these methods may seem like a good idea, there is no scientific evidence to support them.
Eye color is a complex genetic trait that is not as simple as it once believed to be. There are three different genes that contribute to our eye color. These genes control the color of our eyes, but scientists are still unsure why some people have gray or hazel eyes.
Most people have learned about eye color through the dominant/recessive model, which explains that you need only one brown-eyed gene from one parent to be a brown-eyed person (b) but you need two blue-eyed genes from each parent to be a blue-eyed person (bb).
But new research suggests that it might not be so simple. Instead of using a single gene, researchers have found that all blue-eyed people share a mutation in a gene called OCA2.
This gene produces a pigment called melanin, which gives skin, hair, and eyes their color. It’s produced in the iris of the eye, where it filters light and prevents your retina from getting damaged by sunlight.
When you have this mutated gene, the OCA2 protein can’t produce melanin anymore. The result is that your iris becomes lighter in color, which is why it looks blue.
Luckily, this mutation doesn’t completely turn off the production of melanin, so people with blue eyes still have some natural melanin in their iris to help them filter light. This is why black people with blue eyes can have such beautiful eyes.
But the exact cause of this mutation is still unknown. Some experts believe that it may have originated around 10,000 years ago in South-Eastern Europe.
It’s believed that a group of people who possessed blue eyes migrated to these areas, where they began to procreate with other blue-eyed people. This led to the proliferation of the genetic mutation that causes blue eyes.
These individuals then spread across Europe and the world. It wasn’t until recent decades that this mutation became widespread enough to start affecting the entire population of modern humans.
As a result, it’s very rare for black people with blue eyes to be born in this way. But that’s not to say that it’s impossible.
A new study, published in the journal Human Genetics, has revealed that all blue-eyed individuals share a mutation. It was discovered by scientists in Denmark who analyzed the DNA of over 800 people from all over the world.
The researchers found that the gene responsible for generating the blue-eyed phenotype was OCA2. They also found that this ancestry trait was associated with the OCA2 gene in both the European and African populations.