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What Does a DNA Test Tell You
Updated on February 8, 2024
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What Does a DNA Test Tell You
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DNA testing can tell you about your health and how your genes affect it. They can reveal any genetic risk you may have and any genetic disorder you may have inherited or are predisposed to.

About one in seven American adults have used consumer DNA tests.1 They’ve become a popular way to learn more about your identity and find lost relatives.

Below, we’ll discuss what you can learn from genetic testing.

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What You Can Learn About Yourself Through Genetic Testing

1. Physical Characteristics

Physical characteristics or traits are visible features you inherit from your parents. 

You can have various traits, such as your mother’s eyes or your father’s nose. This is why you may notice some similarities when you compare yourself to your parents.

The combination of these traits determines your overall appearance. Here are some physical features you can inherit: 

Hair and Eye Color

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The amount of pigment in your eyes and hair determines their color. Colors that are associated with dominant genes will overshadow the appearance of others.

For instance, brown hair and eyes are dominant traits, which is why many people have them.4

Dimples and Freckles

Dimples can appear if the major muscle in your cheeks (known as the zygomaticotemporal branch or Ztb) is split into two.

Genes that cause dimples are usually dominant. This means you can have dimples even if only one parent has them.5  

Freckles may be genetic, but spending time in the sun makes them more prominent. People with lighter skin are also more likely to freckle than those with darker skin.6

Color Blindness

Color blindness affects your ability to tell some colors apart. The most common gene that causes it is recessive and tied to the X chromosome.

Men can inherit it from their mothers, while women can only get it from both parents with the same genetic changes.

However, keep in mind that there are other types of color blindness that are not related to a person’s sex chromosomes.7

One example is a genetic condition that causes blue and yellow color deficiency.

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Hairline and Balding

Stress, hormonal changes, and poor nutrition may cause balding. But baldness can also be a genetic trait you acquire from your parents.

The major gene responsible for balding is on the X chromosome. This means that men who become bald usually inherit the gene from their mothers.

However, other genes that you inherit from your father may also contribute to hair loss and lead to baldness.8

Skin Tone

The amount of melanin or pigmentation on your skin determines your skin tone. This can vary from fair-skinned to darker skin colors.

If you have one fair parent and another dark-skinned parent, yours might be anywhere in between. This is because multiple genes are responsible for skin color.9 

2. Behavioral Traits

Behavioral traits or behavioral characteristics refer to the way a person acts. Unlike physical traits, they are not as easy to observe.

Genetics partly influences a person’s behavior. Upbringing and your environment can change this over time.

For instance, you may be born left-handed and still learn to use your right hand as you age. Here are some behavioral traits:

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Being Left or Right Handed

Many factors affect the way you inherit handedness. Researchers believe that different genes influence your preferred hand.

You’re more likely to be left-handed if you have a left-handed parent.10

Hand Clasping

Try clasping your hands together. Most people who clasp their hands place their left thumb above the right. 

This response has nothing to do with being left or right-handed. Scientists believe your genes and environment control it.11

Personality

According to a study, kids can inherit 30-60% of their personality traits from their parents.19

It’s why some children act like their parents. The major personality traits are: 

  • Extraversion
  • Neuroticism
  • Agreeableness
  • Conscientiousness
  • Openness

In addition to a person’s DNA, other factors determine your personality. How you are raised, your life experiences, and your parents’ personalities also influence your behavior.12

Although a person’s personality is shaped by genes 20 to 60% of the time, a huge proportion of one’s personality is influenced by the environment.

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Source: 123rf

3. Genetic Predisposition

A person’s DNA sample can reveal their genetic predisposition or risk of developing certain diseases. 

These genes may not directly cause illness. But they can make you more likely to get them. Below are some health risks that are genetically passed down.

Obesity

Specific genes may predispose you to obesity. They can influence your appetite, metabolism, and how your body stores food.13

Your mood, stress levels, and environment also affect your weight. They can affect your eating habits, physical activity, and lifestyle.

Type 1 and Type 2 Diabetes

Your body cannot regulate blood sugar if you have diabetes. There are two kinds:

  • Type 1 diabetes (T1D) causes your immune system to “attack” your pancreas and destroy insulin-producing cells
  • Type 2 diabetes (T2D) usually develops with an unhealthy diet and lifestyle

Type 1 and type 2 diabetes are both genetic disorders. Your genes can increase your risk of developing either condition.14

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Heart Disease

Certain heart diseases may be inherited from parents. You’re at higher risk if your family has a heart attack or coronary artery disease history.

Diabetes and hypertension can also make you prone to heart disease. Healthy eating, exercise, and stress management may lower your risk.15

Hypertension

Your genes may also affect your likelihood of developing hypertension. This is why people with certain ethnicities have a higher risk than others.

If your parents have high blood pressure, you’re also more likely to get it.16

Mental Illness

Mental health conditions may also run in families. Research shows it can increase your risk for:

  • Attention deficit hyperactivity disorder (ADHD)
  • Autism spectrum disorders
  • Depression
  • Bipolar disorder
  • Schizophrenia

However, simply having the genetic mutation isn’t enough to cause problems. Triggers such as traumatic events and stressful situations may activate them.17

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Drug Addiction

Genes can also increase your risk of developing addictions. They determine the amount of dopamine receptors in your brain.

This affects how you respond to addictive substances. People with fewer dopamine receptors are more likely to get addicted than those with more brain receptors.18

This might explain why genetics influence a person’s tendency to smoke, become addicted to tobacco, and ability to quit smoking.18

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What You Can Do With Your DNA Test Results

Your DNA test results can offer you some pretty interesting insights and eye-opening benefits. They can give information about your health, where your ancestors might have come from, and even help you make lifestyle choices.

If you have disease risk from your parents, your genetic testing results can tell you more about them. This information can motivate you to take steps to prevent problems or catch them early. 

Moreover, you can get personalized advice on what to eat and how to exercise based on your genes. Therefore, your genetic test results are like your genetic coach for better health.

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Source: 123rf

An at-home DNA blood test that performs carrier testing can identify genetic risks you might pass on to your children. Your carrier status can help ensure healthy offspring.

Some of the best DNA tests offer ancestry testing. They can estimate your racial background and ethnicity and even help you create a family tree.

If you are curious about your family history, DNA tests can uncover your genetic roots. You might even find relatives you never knew existed.

Finally, maternity and paternity tests check a person’s DNA to confirm their relationship with a parent or child. These tests can be used to support legal cases.

What Does DNA Not Tell You?

While DNA testing gives much information about a person’s genetic makeup and insights about someone’s biology, it doesn’t tell everyone about a person. Here are some things that DNA testing doesn’t reveal:

  • Personal experiences and memories – DNA testing cannot tell about someone's childhood, education, or achievements.
  • Personality traits – While DNA can influence characteristics, it cannot predict them. A combination of genetic, environmental, and experiential factors shapes personality traits.
  • Behavior – Same with personality traits, DNA can influence behavior but cannot predict it.
  • Talent – Same with personality traits, DNA can influence talent, but nurturing it requires practice and environmental factors.
  • Life choices – DNA doesn’t make your life choices for you. Making these decisions involves a lot of free will. So, genetic testing cannot give insights into these things.
  • Future health – DNA can give information about genetic predispositions to specific health conditions, but genetic testing cannot predict with certainty if a person will develop a particular disease.
  • Beliefs and values – These aspects are shaped by personal experiences, upbringing, and cultural influences, not DNA.
  • Depth of relationships – Genetic testing can confirm biological relationships but doesn't show how close you are to each other.
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The Human Genome and Your DNA

People inherit half of their genetic material from both parents. This is how you get physical and biological traits from your mother or father.2

Each gene contains a chain of deoxyribonucleic acid (DNA). DNA contains “instructions” on how your body should produce proteins.

These proteins are essential to your growth, development, and survival. Sequencing these proteins determines your genetic variations and how you express traits.

Your body’s entire genetic code is collectively known as your genome. Genetic testing can help you learn more about your: 

  • Physical traits
  • Behavioral traits
  • Carrier status
  • Health risks

DNA testing companies can also help you build a family tree and discover your genetic ancestry. Of course, this would depend on the services they offer.

How Are Genes Passed From Parent to Offspring?

It all begins with conception. The reproductive cells (sperm and egg cells) from your parents contain half of their genetic information.3

When an egg and sperm cell unite, they form one cell with a person’s entire genetic makeup—half from the father, half from the mother. This cell continues to divide to contain a person’s complete genetic information.

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Updated on February 8, 2024
Ada Sandoval
Ada Sandoval
Content Contributor
Ada Sandoval is a B.S. in Nursing graduate and a registered nurse with a heart for abandoned animals. She works as a content writer who specializes in medical-related articles and pet health.
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