Genetics Glossary: Easy-to-Understand Terms
This is a helpful list of important genetics terms you might encounter in your learning .
Bacteria
Tiny living things made of one cell. Some bacteria are harmful, but many are helpful, like those that aid in digestion.
Example:
Bacteria in your stomach help break down food.
Base (Nucleotide)
The basic "letters" that form the instructions in your DNA: adenine (A), thymine (T), cytosine (C), and guanine (G).
Example:
These four letters are like the building blocks for writing the instructions to create you.
Biodiversity
The variety of life, including different species and ecosystems.
Example:
A forest with many different types of plants and animals has high biodiversity.
Bioinformatics
A field that uses computers to analyze biological information like DNA sequences.
Example:
Scientists use bioinformatics to understand genetic patterns in diseases.
CRISPR-Cas9
A tool that scientists use to edit or change DNA.
Example:
CRISPR is being studied to potentially cure genetic diseases like cystic fibrosis.
Cancer
A disease where cells grow uncontrollably due to changes in their DNA.
Example:
Smoking can lead to DNA changes that cause lung cancer.
Cell
The basic unit of life. All living things are made up of cells.
Example:
Your body is made of trillions of cells working together to keep you alive.
Chromosome
A structure made of DNA that carries your genetic information. Humans have 23 pairs of chromosomes.
Example:
You inherit one set of chromosomes from each parent.
DNA (Deoxyribonucleic Acid)
The molecule that stores all the genetic instructions for building and maintaining your body.
Example:
DNA determines your eye color, hair color, and much more.
DNA Sequencing
The process of figuring out the order of the bases (A, T, C, G) in a strand of DNA.
Example:
DNA sequencing can tell us if someone carries genes for certain diseases.
Embryonic Stem Cell
A type of stem cell that can develop into any cell type in the body.
Example:
These stem cells can become brain, heart, or skin cells, depending on what the body needs.
Epidemic
A disease outbreak that spreads quickly in a specific area.
Example:
If many people in a school get the flu at the same time, it’s considered an epidemic.
Eukaryote
An organism with cells that have a nucleus, like animals and plants.
Example:
Humans are eukaryotes because our cells have a nucleus that contains our DNA.
Evolution
The process by which species change over time to adapt to their environment.
Example:
Giraffes have long necks because their ancestors with longer necks could reach food better, and they survived longer.
Gene
A section of DNA that holds the instructions for making a specific protein or determining a trait.
Example:
The gene for eye color determines if you have blue, brown, or green eyes.
Genotype
The genetic makeup of an organism, or the combination of genes it has.
Example:
If you inherit the gene for brown eyes from both parents, your genotype would be "BB."
Phenotype
The physical appearance or characteristics that result from your genotype.
Example:
If your genotype is "BB," your phenotype would be brown eyes.
Gene Therapy
A medical treatment where doctors change or add genes to fix or replace faulty ones.
Example:
Doctors are exploring gene therapy to treat genetic diseases like muscular dystrophy.
Genetic Condition
A health problem caused by changes or mutations in a person’s DNA.
Example:
Down syndrome is a genetic condition caused by an extra copy of chromosome 21.
Genetic Engineering
Directly altering an organism’s DNA to give it new traits.
Example:
Scientists genetically engineered crops to be resistant to pests, meaning they can survive in harsh conditions.
Genetic Modification
Changing the genes of an organism to produce a desired trait.
Example:
Some fruits and vegetables are genetically modified to grow bigger or resist diseases.
Genetic Testing
A test that looks at DNA to find changes or mutations that could lead to health problems.
Example:
Genetic testing can tell if someone has genes that increase their risk of cancer.
Genome
The complete set of genetic material in an organism.
Example:
The human genome contains all the information needed to build and maintain a person.
Genome Editing
Techniques used to change or correct parts of the DNA.
Example:
Scientists are studying genome editing to find ways to fix genetic mutations.
Genotype-Phenotype Relationship
The way your genotype (genes) affects your phenotype (traits).
Example:
A person with two "B" alleles for eye color (genotype) will have brown eyes (phenotype).
Germline
The genetic material passed from parents to children through eggs or sperm.
Example:
If a mutation is present in the germline, it can be inherited by future generations.
Host
An organism that provides shelter and nutrients to another organism, like a parasite.
Example:
A dog can be a host to fleas, which live on its skin and feed on its blood.
Immunity
Your body’s ability to resist diseases.
Example:
Vaccines help boost your immunity against illnesses like measles.
Model Organism
A species used in scientific research because it’s easy to study and has certain advantages.
Example:
Fruit flies are often used as model organisms in genetic experiments because they reproduce quickly.
Multipotent
A stem cell that can develop into certain types of cells, but not all.
Example:
Blood stem cells are multipotent because they can create different types of blood cells but not muscle or nerve cells.
Mutation
A change in the DNA sequence. It can have positive, negative, or no effect on the organism.
Example:
Some mutations can lead to diseases, while others might help an organism survive better in its environment.
Pandemic
A disease outbreak that spreads across multiple countries or continents.
Example:
COVID-19 was a pandemic that affected people all over the world.
Parasite
An organism that lives on or inside another organism, usually harming its host.
Example:
Tapeworms are parasites that live in the intestines of animals and humans.
Patent
A legal right that gives someone exclusive ownership of an invention or discovery.
Example:
A company might patent a new type of medicine so that no one else can make or sell it.
Pharmacogenomics
A branch of science that studies how genes affect how you respond to drugs.
Example:
Pharmacogenomics helps doctors figure out the best type and dose of medication for each person based on their genetic makeup.
Pluripotent
A type of stem cell that can develop into almost any type of cell in the body.
Example:
Pluripotent stem cells have the potential to become brain, heart, or skin cells, depending on what is needed.
Protein
Molecules made of amino acids that perform many jobs in the body, such as building tissues and organs.
Example:
Hemoglobin is a protein that carries oxygen in your blood.
RNA (Ribonucleic Acid)
A molecule that helps DNA send messages and instructions to the cells.
Example:
RNA is like a copy of DNA's instructions, telling the cell what to do, like making proteins.
Species
A group of living things that can breed with each other to produce offspring that can also reproduce.
Example:
Dogs and wolves are different species because they have distinct characteristics but can still interbreed in certain cases.
Stem Cell
A special type of cell that can turn into other types of cells, such as muscle cells, nerve cells, or blood cells.
Example:
Stem cells could one day be used to repair damaged tissues in people with injuries or diseases.
Transgenic
An organism that has genes from another species inserted into its DNA.
Example:
Scientists create transgenic plants that resist pests by adding genes from bacteria.
Vaccine
A treatment that helps your immune system learn how to fight off certain diseases.
Example:
The flu vaccine helps prevent you from getting the flu.
Virus
A tiny infectious particle that can only reproduce inside a living host cell.
Example:
The common cold is caused by a virus that infects cells in your nose and throat.
Whole Genome Sequencing
The process of reading an organism’s entire genetic code.
Example:
Whole genome sequencing can help identify genetic disorders by analyzing all of a person’s DNA.
X-ray Photography
A technique that uses X-rays to take pictures of the inside of objects, like bones or organs.
Example:
Doctors use X-ray photography to see if you have a broken bone.