Start here. Genetics from the beginning.
Genes, explained in five minutes.
No PhD required. No jargon. The most-asked questions about genes, DNA, inheritance, and genetic testing - answered as plainly as we can manage, reviewed by people who actually know. Free for everyone, forever.
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Ordered by what beginners ask first. Each door leads to a filtered list of questions and the key terms behind them.
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The 7 most-asked questions about genes
If you read nothing else, read these. They cover the foundations everything else builds on. Each answer starts with one plain sentence - the whole truth in brief.
- 1
What is a gene?
A gene is a short stretch of DNA that carries the instructions for one specific job in your body — usually, building a particular protein.
- 2
Are genes and DNA the same thing?
No. DNA is the material; a gene is a section of it. All genes are made of DNA, but not all DNA is genes.
- 3
How do genes actually work?
Genes work by telling your cells which proteins to make, and proteins do almost all the real work of keeping you alive.
- 4
Can my genes change during my life?
Your core DNA sequence stays essentially the same for life, but which genes are switched on or off changes constantly.
- 5
Are all my traits decided by genes?
No. Genes influence almost everything about you, but for most traits the environment matters just as much.
- 6
What is a gene variant?
A gene variant is a small difference in a gene's spelling that makes one person's version slightly different from another's.
- 7
How is a gene test actually done?
You give a saliva or blood sample, a lab reads specific points in your DNA, and a report tells you what those points say.
The vocabulary
20 key terms, each in one plain line
The words that come up again and again - defined plainly, with an everyday example.
See the full glossaryTruth or trash
8 common gene myths
Genetics attracts more confident nonsense than almost any field. Each myth gets a plain verdict and the actual truth.
Read the myth-buster- TrashYour genes are your destiny.
- TrashWe use most of our DNA to make proteins.
- TrashThere's a single gene for intelligence, happiness, or athletic ability.
- Mostly trashIdentical twins are genetically identical for life.
Why you can trust this
Editorial standards
Every answer here is researched against trusted sources, written in plain language, and reviewed by someone with genetics training before it goes live. We cite where it matters, we update when the science updates, and we say so when something is still unknown. The date of last review appears under each answer.
- Researched against trusted sources
- Reviewed before publishing
- Updated when the science updates