Genes are the basic units of heredity, and they’re the blueprints for making the proteins that not only make us unique but also are responsible for doing the work of life. We have structural proteins (that make up things like skin and muscle cells) and we have functional proteins (those that interact with other molecules to perform a function, like digestive enzymes and certain hormones).
Genes are made of strands of deoxyribonucleic acid (DNA). DNA has a unique helical structure and wraps up on itself in huge quantities to form chromosomes.
When the body needs to make proteins, the first step is to make a very similar copy of the genetic information in a single strand called ribonucleic acid (RNA). This process is called transcription. Transcription is controlled by segments of DNA called promoter regions, which are like traffic signs that tell the cell: the DNA sequence that follows codes for a protein.
The RNA copy that was just made is transported to another intracellular structure called a ribosome, where genetic information is translated into proteins. This part of the process is called, rationally enough, translation.
Sometimes the nucleic acids contained in DNA are mistakenly copied, changing the protein-coding information (a mutation). Mutations are responsible for the huge diversity that we see between dog breeds and even within golden retrievers. Unfortunately, mutations also may lead to disease. Some of the goals of this study are designed to better understand this last part.
As scientists understand more about genetics, we realize that genes and genetic disease are only part of the story that DNA has to tell. We’ll talk more about that in our next Science 101 article, when we focus on an exciting new area of research called epigenetics.