Born This Way? Or Made This Way? The Truth About Genetics and Socialization

Genes, Childhood, and the Environments That Shape Us

When I first started learning about child development, I thought the big question was simple: are we born the way we are, or does life make us that way? Pretty quickly, I realized the answer is both—and the real story is how genes and environment constantly talk to each other.

Temperament: The Starting Point

Think about babies you know. Some are chill from day one. Others scream at every new sound or face. Psychologist Jerome Kagan studied this in the 1980s and found that about 20% of infants were high-reactive—they kicked and cried a lot when something new happened. Many of those kids later became “slow-to-warm” or shy, but not all of them.

That’s the key lesson: genetics can set a starting point, but it doesn’t lock in the outcome. A baby who seems timid early on can grow into a confident adult if they get the right encouragement and support.

How Brains and Emotions Fit In

Our genes also play a role in things like memory, language, and how easily we handle stress. All of that shapes how kids fit into social life.

• If you’re quick with words, it’s easier to join conversations and make friends.
• If you’re prone to anxiety, you might hang back and miss chances to connect.

Twin studies suggest that traits like sociability are about 40–50% influenced by genetics. But that doesn’t mean “half of your personality comes from your DNA.” What it really means is that, across a big group of people, genes explain a chunk of the differences we see. The rest comes from life—families, peers, school, culture.

One example I find fascinating: some kids carry a gene variant that makes them extra sensitive to feedback. If they get warm, supportive parenting, they often become especially social. If they grow up with harsh or critical parenting, the same gene makes them more withdrawn. Same card, totally different game depending on the environment.

Nature and Nurture Dancing Together

You might have heard about the so-called “warrior gene” (MAOA). Early studies suggested that kids with a certain variant were more likely to show aggression if they also grew up in really tough environments. But later studies showed the effect was pretty small, and most kids with the gene never turned aggressive.

It’s a good reminder that genes tilt the odds; they don’t decide the future.

Experience Can Change Biology

Here’s where things get even wilder: experiences can literally affect how genes are used. This is called epigenetics.

• Kids who grow up with nurturing caregivers may have stress systems that calm down more easily.
• Kids who grow up in unpredictable or unsafe environments may develop stress systems that stay on “high alert.”

Scientists have found changes in genes like NR3C1 and FKBP5 that help explain why. Even brain growth factors like BDNF, which support memory and learning, can be influenced by stress. Long-term stress can make it harder for the brain to build new connections, which may explain why adversity sometimes affects school performance and emotional resilience.

What amazes me is that some of these changes can last for years, and studies in animals suggest they might even carry into the next generation.

Childhood as Our Apprenticeship

One thing that sets humans apart from other animals is our very long childhood. We’re dependent on adults for years, which gives us a long stretch of time to absorb language, culture, and social rules.

Sometimes I think of it like nature giving us an extended apprenticeship in “how to be human.”

Culture Matters Too

It’s tempting to think genes work the same way everywhere, but context matters.

• In wealthier, more equal societies, genetic influences often look stronger because kids’ environments are fairly similar.
• In more unequal societies, environment makes a bigger difference, because kids’ experiences are so different.
• Parenting styles vary too: Dutch parents often encourage independence and open conversation, while in Kenyan villages, kids take on responsibilities earlier and get support from extended families. Each style interacts differently with kids’ biology.

So, biology may be universal, but the way it shows up is always filtered through culture.

The Big Takeaway

Genetics gives us a starting point. Environment shapes the path. Neither works alone—they’re in constant conversation.

If you’re shy, that’s not a curse; it’s just where you begin. If you’re outgoing, it still takes practice and guidance to turn that into healthy relationships. And for all of us, the way we’re raised, taught, and supported leaves marks—not just on our behavior but sometimes even on how our biology works.

👉 Remember for class discussions:

• Genes set up tendencies, not destinies.
• Early environments matter, but so do middle childhood, adolescence, and culture.
• Experiences can leave biological fingerprints through epigenetics.
• Context (family, society, culture) always changes the picture.

That, to me, is hopeful. Every stage, every interaction, every relationship has power to shape who we become.

References

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