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The GeneEd website is scheduled to be retired on March 31, 2019. Selected GeneEd content will be transferred to Genetics Home Reference, another online resource from the National Library of Medicine.

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Genetic Code

Genetic Code

ACGTis an acronym for the four types of bases found in a DNA molecule: adenine (A), cytosine (C), guanine (G), and thymine (T). A DNA molecule consists of two strands wound around each other, with each strand held together by bonds between the bases. Adenine pairs with thymine, and cytosine pairs with guanine. The sequence of bases in a portion of a DNA molecule, called a gene, carries the instructions needed to assemble a protein

Genetic Code
Images and animations are courtesy of the National Human Genome Research Institute's Talking Glossary (

Materials for Genetic Code


The Animated Genome

Description: An engaging 5 minute film about DNA and the human genome that is sure to please.


How Do You Identify the Genes in a Genome?

Description: After the sections of DNA sequence have been assembled into a complete genome sequence we need to identify where the genes and key features are, but how do we do this?

Revealing DNA as the Molecule of Life

Description: How was DNA discovered to be the carrier of genetic information? Read on to find out...

The Discovery of DNA

Description: How was DNA first discovered and who discovered it? Read on to find out...

What Does DNA Do?

Description: The DNA code contains instructions needed to make the proteins and molecules essential for our growth, development and health.



Description: This game combines the challenge of a scavenger hunt with the human genome. It allows anyone to create up to 20 walkable paths that explore the human genome with over 150 challenging questions, a leaderboard and themed paths. GenomeCache combines clues, fun facts and trivia questions to create an engaging learning experience.

Interactive Tutorials

Build a DNA Molecule

Description: Practice building a DNA molecule using this interactive tutorial on complementary base paring of DNA nucleotides.

DNA Mapping Web App

Description: DNA Mapping is a free web tool to locate and map enzyme cutting sites of your DNA sequence. You can enter your DNA sequence and it will help you to find the location of specific restriction enzymes. You can also use the web app to get the list of single, double or no cutting enzyme lists. It is a useful tool for both students and professionals who study or research in molecular biology or other biological related sciences. It makes your molecular cloning experiment simple and straightforward.

DNA Sequence Editor Web App

Description: DNA Sequence Editor is a free web tool to analyze and edit your DNA sequence. Enter your DNA sequence and you can get the reverse, complementary or transcription sequence of your DNA. It can also translate your DNA sequence into possible amino acid sequences. It also help you to predict the DNA enzyme digestion result. Just select an enzyme from the list and you can get the size and sequence of each restricted DNA fragment. It is a useful web tool for molecular biology students and professionals. It is a great help for your molecular cloning work.

DNA Words are Three Letters Long

Description: An interactive Web site exploring basic concepts of the genetic code through historical discovery

Labs & Experiments

Gel Electrophoresis

Description: Build your own gel electrophoresis device from scratch with simple materials, and use electricity to separate colored dyes. Gel electrophoresis is a powerful technique used to manipulate and analyze DNA.

Restriction Analysis

Description: A DNA virtual laboratory experiment

Teacher Resources

Cracking the Genetic Code (Lesson Plans/Lesson Activities)

Description: This lesson explores what the knowledge of DNA can tell us about ourselves and other organisms and species.

Decoding the Flu (Lesson Plans/Lesson Activities)

Description: This classroom activity teaches how to read and interpret information stored in DNA. It makes use of personal response systems (clickers) and a PowerPoint presentation. The story centers on a CDC student intern, Jason. While working with a CDC team in Mexico, Jason is the only person who does not get sick from a new strain of flu. It is up to Jason to use molecular data collected from different local strains of flu to identify which one may be causing the illness.

Sequence Bracelets

Description: In this activity you can make a bracelet of DNA sequence from organisms including a human, chimpanzee, butterfly, carnivorous plant or flesh-eating bacteria.

Yummy Gummy DNA

Description: Make your own edible DNA double helix out of sweets.


Molecular Basis of Heredity: Part 1. Nucleic Acids

Description: Discover the fundamentals of DNA, RNA, nucleic acids and their roles within cells, with Raye Lynn Alford, PhD.

Chemical Components of DNA ACTG


DNA Molecule - Chargaff Ratios

Description: Erwin Chargaff found that in DNA, the ratios of adenine to thymine and guanine to cytosine are equal. Watch this short animation to see illustrated these balanced ratios of base pairs.


DNA Sequencing Game, Interactive 2D Animation

Description: Use DNA fragments to reconstruct a piece of DNA in this simple and quick game.

Gene Boy

Description: An interactive bioinformatic toy for analyzing DNA sequence data

Interactive Tutorials

Gel Electrophoresis Virtual Lab

Description: An interactive tutorial on using gel electrophoresis to measure DNA strands