This blog is about the story of my family here in America. We arrived in the 1630s as Puritans, and became the common folk of the New World.

Why you have blue eyes even if both your parents have brown eyes

Usually when you combined any two plants or animals, you get something that looks either like both of them, or like one in particular, and shades in between. This is determined by genes, which are the blueprint of what we will look like and are contained in our cells. If you don't look like your parents, it's no cause for suspicion as to your being their genetic descendent. If, for example, both of your parents, like mine, had brown eyes, and you have blue eyes, it is because of something called a *recessive gene*.

Certain genetic traits are dominant, and some are recessive. The dominant ones are, as the name implies, more likely, and the recessive ones *hide* a bit in the background. The classic example is parents with dominant genes, such as brown eyes, having a child with a recessive gene, blue eyes.

The chances, mathematically, of getting a recessive gene like blue eyes from parents who have dominant genes, is four in one. Keep in mind that is just a mathematical model. Brown-eyed people can have hundreds of brown-eyed children before the blue-eyed one pops up. It's a mathematical possibility, that's all. My family did the mathematical model perfectly. I have three brothers, all with brown eyes, the children of brown-eyed parents. I got the recessive gene, which gave me blue eyes.

Now, keep in mind that it doesn't work the other way around. Since I am carrying only a recessive gene for eye color, if I ever had a child with a blue-eyed woman, the child could only have blue eyes. If the woman had brown eyes, there would be a chance of having a brown-eyed child, but with two carriers of recessive genes, there is no longer a chance of getting back that dominant gene.

Genetics are complex things, which create the diversity and richness of life on planet earth.

Be gentle with yourself. You are a child of the universe no less than the trees and the stars; you have a right to be here.
- Max Ehrmann


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