Why is it different from what they had when your son was born? In which month of life will the final tone be set? Is it possible that they are blue if both you and your partner have them dark?
Now that your baby is growing, it is interesting to see that as the weeks go by, his eyes lose the bluish gray color they had when he was born. Why the change?
An inherited trait
Your child’s definitive eye tone will depend on the amount of melanin (substance responsible for the color) your iris has. This characteristic, as with other features of the baby, is already determined from the moment of fertilization, depends on the genetic information received by the child and several genes are involved in it.
But if he was born with clear eyes…
But if it is a trait that is inherited, why do most babies reach the world with clear eyes? The reason is very simple. In newborns, melanocytes (the cells responsible for producing melanin) are still immature and do not perform their function well: that is why during the first months of the baby’s life the iris has this substance in small amounts.
As the child grows and his eyes are exposed to sunlight, the melanocytes will increase their activity and pigment the iris until it reaches its final tone, something that will occur at approximately 6 months of age. And it will be at that moment when the influence of genetic inheritance becomes apparent.
What will be its final color?
To give you an idea of what its final color will be, if both you and your partner have clear eyes, it is likely that your child will have them as well. In that case, the initial tone will simply become nuanced with time, but it will not disappear. On the other hand, if the eyes of one of you are brown or black and those of the other are blue or green, for example, the most common is that the child has them dark, since the gene that determines the dark color is dominant against the which gives rise to light color.
However, you should keep in mind that the influence of other genes on this physical trait means that these calculations cannot be 100 percent determining.
The genetics department at Stanford University has designed a tool to find out the color of a child’s eyes. Of course, they warn that it is not infallible, because the system is based on the fact that this physical trait depends on two genes, when in reality there may be others involved. Click here to see it.
And what about the hair color?
It is also a genetically inherited factor (the dark color gene is dominant and the light gene is recessive). And as with the tone of the eyes, it is very common for the initial to change. It is due to several factors:
- As the melanocytes mature and produce more melanin, this substance darkens the hair.
- With the passage of time the sebaceous glands increase the production of fat, which gives a darker appearance to the hair. And keratin is also increased in the body, a substance with a similar effect.