why are my eyes the colour they are?

What determines eye color is the pigment melanin. Eyes that have a lot of it in the connective tissue at the front of the iris, called the stroma, are darker, while those that have less tend to be lighter.

The levels of melanin generally remain the same throughout life, but a few things can change them permanently.

The first is a handful of ocular diseases like pigmentary glaucoma. Another is a condition called heterochromia, or multicolored eyes, which affects about 1 percent of the population and is often caused by traumatic injuries. An example of this can be seen in the rock star David Bowie, who attributes his contrasting eye colors, hazel and light blue, to a blow to the face as a child.

The third cause appears to be genetics. A study in 1997, for example, looked at thousands of twins and found that 10 percent to 15 percent of the subjects had gradual changes in eye color throughout adolescence and adulthood, which occurred at nearly identical rates in identical twins.

Can it really change for no apparent reason?

In most people, the answer is no. Eye color fully matures in infancy and remains the same for life. But in a small percentage of adults, eye color can naturally become either noticeably darker or lighter with age.

THE BOTTOM LINE Eyes can change color in some people because of genetics or injury.

Cheers

Eyes being dark or light has to do with a recessive light gene and a dominant light gene. There are separate genes responsible for the exact coloration of an eye. Your mother is (bb), that is, homozygous recessive, as are you AND all your brothers, apparently. Your father is heterozygous (Bb), since he has brown eyes. He must be heterozygous because you seem to be getting his recessive b.

The exact coloration is not nearly so simple. One of two things is happening. You either have a mutation (most likely) causing different phenotypes (visible traits) to show up all at once, or you have an extremely unlikely chain of DNA that causes all the colors to show. The former is much more likely, however. Not a big deal, looks cool anyhow.

Please, answer my question:

http://answers.yahoo.com/question/index;_ylt=Aq9HI...

long que

my ans --- secret lies in genes-dna-chromosomes ....consult a scientist