Facts About Eye Color
What will be the eye color of a newborn baby who has one parent with brown eyes and the other parent with blue eyes? Questions like this are among the first to enter the minds of soon-to-be-parents. But the answer is not all that simple. It all comes down to a complex system of genes that combine in various ways to determine such characteristics as eye and hair color.
Pigmentation
The iris contains the colored pigment that determines a person's eye color. According to AllAboutVision.com, many babies' eyes change color as they grow older. It is common for a baby's blue eyes to change to brown in about a 3-year period as the brown pigment (known as melanin) becomes present later in life. It is uncommon for melanin to be present in newborns.
Genetics
According to AllAboutVision.com, three genes contribute to the color of a person's eyes. Research has gathered ample information about two of these genes responsible for the most common green, brown and blue eye colors. Not enough definitive research has been attained to explain the occurrence of less common eye colors, such as gray, hazel and other mixtures. The formation of eye color is a complex, scientific issue that involves multiple possibilities of combinations of genes received from both parents. According to AllAboutVision.com, each cell in a person's body is made up of 23 chromosomes from the mother and 23 chromosomes from the father, with each parent passing on two pairs of genes per one chromosome.
Possibilities
A person can have a different eye color than both parents, but a child will most likely have brown eyes if both parents do as well. Generally, the genes that present darker eye colors surpass the lighter ones. A brown gene normally dominates a green gene, while a green gene normally dominates a blue one. Even this theory is not foolproof. A child does not necessarily have brown eyes if one parent has brown and the other parent has blue eyes. It is more common for a blue-eyed child to have both parents with brown eyes than a brown-eyed child to have both parents with blue eyes, although this situation can occur. It is also possible to have eyes of different colors. This can be caused by pigmentation problems, trauma, inflammation, genetic disorder, freckle of the iris or Horner's syndrome.
Changes in Eye Color
A person's eye color can change. The iris responds to pupil size. If the pupil enlarges, the pigments spread out, causing a lighter color. If the pupil gets smaller, the pigments push together, causing a darker color. Age is also a factor in a change of eye color. AllAboutVision.com states that 10 to 15 percent of Caucasians experience a change of eye color (either darker or lighter) as they grow older. If a drastic color change occurs, make an appointment with an eye doctor to make sure it is not indicative of disease. Colored contacts are the only certain way to change eye color; however, a prescription from an eye doctor must be obtained to guarantee the use of safe lenses.
Interesting Facts
According to EyeDoctorGuide.com, the predominant eye color around the world is brown. The guide also reports that Asians, Africans and Native Americans often have black eyes, while Europeans often have hazel (a combination of green and brown) or blue eyes. Green eyes are found mainly in people of German or Slavic descent.
Tags: blue eyes, both parents, brown eyes, change color, According AllAboutVision, both parents with
