How eye color is passed from parent to child. Calculate the color of the eyes of the child.
Eye color is a characteristic determined by pigmentation of the iris. Eye color is a charming and interesting topic that has fascinated numerous researchers over the centuries, until science helped us better understand the nature of the origin of eye color, and most importantly, how it is inherited.
When it comes to predicting the color of the baby’s eyes, one thing is certain - the baby will be born with blue eyes. Almost always, the eyes of newborns are precisely blue in color, which subsequently darkens as exposure to sunlight. By about three or four years old, the child’s eyes usually acquire their permanent, lasting color, whether they are blue, green, brown, amber, gray, dark brown or even dark red .
We hope that future parents will use this article as a kind of help to determine the color of their baby’s eyes. It doesn’t matter whether you delve into the scientific theory regarding the prediction of eye color in children, these tips are intended to be an excellent basis for determining the color of the child’s eyes for expectant mothers and fathers. Use it as an assistant to the emergence of a reasonable forecast based on long hours of research.
The iris consists of the anterior - mesodermal and posterior - ectodermal layers.
The anterior layer consists of the outer border region and the stroma. Chromatophores containing melanin are distributed in it. The color of the eye depends on the nature of the distribution of pigments in this layer.
The back layer contains many pigmented cells filled with fuscin. Regardless of the color of the eyes, the back layer is dark in color, with the exception of only albinos. In addition, the role of vessels and fibers of the iris.
Science color inheritance
The question of eye color and how it is passed on from parents to offspring has been a topic of much debate among geneticists for many years. There is an established opinion that the color of the eyes of a child is inherited according to the laws of Mendel. According to this law, eye color is inherited in almost the same way as hair color: dark-colored genes are dominant, i.e. the distinctive features (or phenotypes) encoded by them take precedence over the distinctive features encoded by the lighter color gene.
Parents with dark hair are more likely to have children with dark hair; descendants of fair-haired parents will be fair-haired; and the child of the parents, whose hair color is different, will have hair, the color of which will be somewhere in between the parent. Of course, there are exceptions, but there are also patterns of processes described by Darwin, Lamarck, and Mendel a century ago. There are also rules that describe code and inheritance for most genes.
Some fun facts about eye colorone
You probably know that brown is considered the most common eye color in the whole world, but did you know that the rarest eye color is green? In fact, less than two percent of the world's population has green eyes. Speaking about countries separately, Turkey has the highest percentage of citizens with green eyes, namely: 20%. There are also a certain number of countries located mostly in Asia, South America and the Middle East, whose inhabitants have almost no green eyes.2
Do you know that for residents of the Caucasus, blue eye color is the most characteristic, not counting amber, hazel, gray and green? Also, more than 80% of the inhabitants of Iceland have eye color either blue or green.3
A not very common, but very noticeable phenomenon, called heterochromia, leads to the fact that the eyes of a person have a completely different color. The American actress Mila Kunis, known for the series “The Show of the 70s” and “Family Guy,” has one blue eye and the other green. Kate Bosworth, who played in Blue Wave and Superman Returns, has both blue eyes, but the lower part of her right eye contains a large interspersed brown color. David Bowie, author of the hits Ziggy Stardust and Labyrinth, is perhaps the most famous celebrity with a different eye color. However, few people know that the difference in the color of Bowie's eyes is the result of an injury that he received as a teenager during a game of football, and not heterochromia.
Eye color from grandparents - is transmitted genetically to our grandchildren.
Tables for calculating the color of the eyes of an unborn child
Eye color from grandparents - is transmitted genetically to our grandchildren. During pregnancy, many parents are eager to find out what color their eyes will have their unborn child. All answers and tables for calculating eye color are in this article. The good news is for those who want to convey to their descendants exactly their eye color: this is possible. Recent studies in the field of genetics have discovered new data on genes that are responsible for eye color (previously 2 genes responsible for eye color were known, now there are 6). At the same time, genetics has no answers to all questions regarding eye color. However, there is a general theory that, even with the latest research, provides a genetic justification for eye color. We will consider it.
So: each person has at least 2 genes that determine eye color: the HERC2 gene located on the 15th chromosome of a person, and the GEY gene (also called EYCL 1 ), which is located on the 19th chromosome .
A person has two copies of this gene, one from his mother, one from his father. HERC2 happens to be brown and blue, that is, one person has either 2 brown HERC2 or 2 blue HERC2 or one brown HERC2 and one blue HERC2:
HERC2 gene 2 copies *Brown and brown
Brown and blue
Blue and blue
Human eye colorBrown
Blue or green
Where the owner of two blue HERC2 comes from is the green color of the eyes explained below. In the meantime, some data from the general theory of genetics: brown HERC2 is dominant and blue is recessive, so the carrier of one brown and one blue HERC2 will have brown eyes. However, the carrier of one brown and one blue HERC2 with a 50x50 probability can transmit both brown and blue HERC2 to their children, that is, the dominance of brown does not affect the transmission of a copy of HERC2 to children.
If the wife has brown eyes, even if they are “hopelessly” brown - that is, she has 2 copies of HERC2 brown, all children born with such a woman will be brown-eyed, even if the man has blue or green eyes, as she will pass them on to the children one of his two brown genes. But grandchildren can have eyes of any color.
HERC2 from the mother is brown (in the mother, for example, both HERC2 are brown)
HERC2 from the father is blue (for the father, for example, both HERC2 are blue)
HERC2 in a child is one brown and one blue. The color of the eyes of such a child is always brown; at the same time, he can transfer his blue HERC2 to his children (who can also receive blue HERC2 from the second parent and then have eyes either blue or green).
Now let's move on to the GEY gene
It happens green and blue (blue, gray), each person also has two copies: a person receives one copy from his mother, the second from his father. Green gey is the dominant gene, blue gey is recessive. A person, therefore, has either 2 blue gey genes or 2 green gey genes or one blue and one green gey gene. At the same time, this affects the color of his eyes only if he has HERC2 from both parents - blue (if at least one of his parents received HERC2 brown, his eyes will always be brown).
If a person receives a blue HERC2 from both parents, depending on the gey gene, his eyes may be in the following colors:
GEY Gene: 2 copies
- Green and green
- Green and blue
- cyan and cyan
Human eye color
The general table for calculating the color of the child’s eyes, brown eye color is indicated by “K” , green eye color is indicated by “Z” and blue eye color is indicated by “G” :
Using this table, we can say with a high degree of probability that the child’s eyes will be green, if both parents have green eyes or one of the parents has green eyes and the other has blue eyes. You can also say for sure that the child’s eyes will be blue if both parents have blue eyes. If at least one of the parents has brown eyes, their children may have hazel, green or blue eyes.
- two brown-eyed parents have a 75% chance that their child will have brown eyes, 18.75% green and 6.25% blue.
- if one of the parents is brown-eyed and the second green-eyed, the probability that the child will have brown eyes is 50%, green - 37.5%, blue - 12.5%.
- if one of the parents is brown-eyed and the second is blue-eyed, the probability that the child will have brown eyes is 50%, blue - 50%, green - 0%.
Thus, if the child’s eyes are not the same color as his parents, there are genetic reasons and justifications, because "nothing disappears without a trace and nothing comes from nowhere"
The outer layer of the vessels of the iris, formed from collagen fibers, is distinguished by a dark blue color. If the fibers of the external ectodermal layer of the iris are of low density and low melanin content, then it has a blue color. In the iris and in the eye there are no blue or blue pigments at all. Blue color is the result of light scattering in the stroma. The inner layer of the iris, unlike the outer one, is always saturated with melanin and has a black-brown color. As a result, part of the high-frequency component of the spectrum of light incident on the eye undergoes scattering in the turbid stromal medium and is reflected, and the low-frequency component is absorbed by the inner layer of the iris. The lower the stroma density, the richer the blue color. This color has many babies in the first months of life.
Unlike blue eyes, in this case, the density of collagen stromal fibers is higher. Since they have a whitish or grayish tint, the color will no longer be blue, but blue. The higher the density of the fibers, the brighter the color. Blue eye color is the result of a mutation in the HERC2 gene, due to which the carriers of this gene have reduced melanin production in the iris of the eye. This mutation occurred about 6-10 thousand years ago. Blue and blue eyes are most common among the population of Europe, especially in the Baltic States and Northern Europe. In Estonia, up to 99% of the population have such eye color, in Germany - 75%. In Denmark in the 1970s only 8% had dark eye color, while now, as a result of migration, this figure has increased to 11%. According to a 2002 study, among the Caucasian European population born in 1936-1951, carriers of blue and blue eyes make up 33.8%, while this indicator is 54.7% among those born in 1899-1905. According to 2006 data, this figure for modern white Americans fell to 22.3%. Blue and blue eyes are also found in the Middle East, for example, in Afghanistan, Lebanon, and Iran. They are also common among Ashkenazi Jews, for example, among Ukrainian Jews, the percentage of carriers of these flowers is 53.7%.
Gray eye (steel shade)
The definition of gray and blue eyes is similar, but the density of the fibers of the outer layer is even higher and their hue is closer to gray. If the density is not so high, then the color will be gray-blue. The presence of melanin or other substances gives a slight yellow or brownish admixture. The gray color is supposedly associated with Mie scattering on the fibers of the outer layer, which, unlike Rayleigh, is less dependent on the wavelength; as a result, the spectrum of light reflected from the iris is closer to the source spectrum than in the case of blue or blue eyes. Gray eye color is most common in Eastern and Northern Europe. For Russians, this color, according to 1909, reached 50%. It is also found in Iran, Afghanistan, Pakistan and some regions of North-West Africa.
The green color of the eyes is determined by a small amount of melanin. In the outer layer of the iris, yellow or light brown pigment lipofuscin is distributed. In total with the resulting blue or blue resulting from scattering in the stroma, green is obtained. The color of the iris is usually uneven and there are a lot of different shades. In its formation, perhaps, the gene of red hair plays a role. Pure green eye color is extremely rare. Its carriers are found in Northern and Central Europe, less often in Southern Europe. According to studies of the adult population of Iceland and the Netherlands, green eyes are more common in women than in men.
Amber eyes have a monotonous light yellow-brown color. Sometimes they are characterized by golden green or
Swamp green Swamp eye color is a mixed color. Depending on the lighting, it may have a golden, brown-green, brown hue. In the outer layer of the iris, the content of melanin is quite moderate, so the marsh color is obtained as a combination of brown color, which gives melanocytes, and blue or blue. Yellow pigments may be present. Unlike amber, in this case, the color is not monotonous, but rather heterogeneous. In some cases, the color of the eyes may not seem so much as marsh (brown-green), but light brown with a yellow-green hue, therefore in the English tradition it is called hazel (English hazel), and in Polish - beer (English piwny).
In this case, the outer layer of the iris contains a lot of melanin. Therefore, it absorbs both high-frequency and low-frequency light, and the reflected light in total gives brown. Brown is the most common eye color in the world. It is ubiquitous in Asia, Oceania, Africa, South America, as well as in Southern Europe.
The structure of the black iris is similar to brown, but the concentration of melanin in it is so high that the light incident on it is almost completely absorbed. In addition to the black iris, the color of the eyeball may be yellowish or grayish. This type is distributed primarily among the Negroid race, in South, Southeast and East Asia. In these regions, newborns are immediately born with a melanin-rich iris.
What will your unborn child look like (Infographic)
Who your children will look like is incredibly curious to know, isn’t it? Science today works wonders and can easily predict which family traits will be passed on to the unborn baby.
The site Bright Side analyzed the genetic patterns and made approximate portraits of children from parents of different types of appearance.