.Not Just for Kids

Who You Are Is In The Genes

Do you have freckles? How about dimples? Can you curl your tongue? These are just some of the traits given to you by your parents.

Some of the traits are dominant and some are recessive. A dominant trait

dominates over a recessive trait. For example, in people, we get one piece of information from each of our

parents, called a gene. The different shades or kinds of a gene are called alleles (say ah-leels). Now let's say your mom gives you an allele for blue eyes, and your dad gives you one for brown eyes. Brown is dominant and blue is recessive, so you will have brown eyes.

Here are more dominant traits:

• dimples
• freckles
• cleft (an indent in the middle of your chin)
• widow's peak (Look at where your forehead meets your hairline. If there is a point, you have a widow's peak.)

Sometimes alleles are codominant. Blood type is one example. If you get Type A from your mom and Type B from your dad, you won't be just one or the other - you'll be Type AB! Neither type is dominant, so both types show through.

And then there's incomplete dominance. This is more like a compromise. One example is in the snapdragon plant. If a plant is made from a white-flowered plant and a red-flowered plant, guess what color its flowers will be? Pink! With incomplete dominance, neither kind is more dominant.

Check out the science side of plants in this week's feature story.

Be a Geneticist

Meet the aliens Mendelians. Mrs. Mendelian and Mr. Mendelian are about to have a baby alien. They want to know what color their baby will be.

Mr. Mendelian is blue.

Mrs. Mendelian is yellow.

If blue is dominant and yellow is recessive, what color will the baby be? Color the baby alien on the left.

If the two colors have incomplete dominance, what color will their baby be? Color the baby alien on the right. Check your colors below.

Clue in on Fingerprints

Look at your fingertips very closely. There are small indents in rows, which sometimes swirl into circles or ovals. These fingerprints are yours alone; no one else has a set exactly like them.

Even identical twins have different fingerprints. Why is this? Well, two things determine the pattern your fingerprints have. For one, the genes your parents passed on to you help decide the shape. But there is something else. When babies are about 6 weeks old, still inside their mom, their fingers are very sensitive to movement. And how they move changes their fingerprints.

Answers: If blue is dominant, the baby will be blue. If the colors have incomplete dominance, the baby will be green!

| Back to Archives |

VolumeVI Number 32
August 13-19, 1998
New Bay Times

| Homepage |