How Two Brown-Eyed Parents Can Have A Blue-Eyed Baby
Blue eyed babies can sometimes seem to spring out of nowhere, especially if there is no known occurrence of blue eyes on the mother’s or father’s side. This has made some concerned parents question where the blue eyes could have come from, especially if both parents have brown eyes.
People with blue eyes are all said to have the same form of the mutated gene responsible for eye pigmentation. Since this gene isn’t exactly an ‘original’, it’s very easy for it to get overlooked when genes are passed down from one generation to the next.
Truth is, there are a number of colors that lie behind brown eyes. This is possible due to the different genes that are linked to eye color. The most common eye color is brown, while the rarest is green, and shades of hazel, gray and blue usually lie somewhere in between. Brown eyes are an indication of the presence of a dominant gene. This gene is responsible for the pigmentation in the eye, and in its presence, more pigment is produced, thus the brown eyes. The gene responsible for blue eyes, however, is actually a recessive gene. This means that in the presence of a dominant gene, it will be trampled over. The recessive gene causes less pigment to be produced in the eye, and blue eyes are an indication of the least amount of pigment being produced. The blue-eyed gene can be passed down from one generation to the next without manifesting itself, waiting for the ‘best’ time to appear, which is when two carriers of the gene have children.
Two brown eyed parents could be carriers of the recessive gene that causes blue eyes. This is because brown eyes are only an indication of the presence of the dominant gene. This gene will still manifest its traits in the presence of a recessive gene, which in this case is the blue-eyed gene. Everyone inherits two copies of genes from both of their parents, and the copies could be different or the same. In the case of carriers of the blue eyed genes, the copies of the genes inherited by the children are different.
Let’s say that the recessive gene is the ‘clear’ gene, and the brown-eyed gene is ‘brown’. When these two combine, the brown gene is what will be manifested. However, there are two copies of the ‘clear’ gene courtesy of both parents. If these two copies combine, then one of the children will have blue eyes. It’s important to note that each of the children has a 25% chance of having blue eyes if both parents are carriers of the gene.
In conclusion, it’s possible for two parents with brown eyes to have a child with blue eyes. The gene can remain hidden within the family tree for very many years, and shouldn’t be a cause for concern. It’s important to note that there are a number of genes that are responsible for the manifestation of eye color. Therefore, one can’t really predict when or if the blue eyes will appear.