1.1: Two definitions of the word "gene"
- Page ID
- 141888
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Genetics is the study of genes -- you may (or may not) have noticed in your introductory course that the word "gene" means one thing or another depending on the context:
- A gene is a particulate unit of inheritance. This is the way Mendel and Morgan studied genes -- "things" transmitted from parents to offspring and carried by chromosomes. We call this view classical or transmission genetics.
- A gene is a region of DNA that codes for a protein. This was the way Beadle and Tatum studied genes, the view of molecular biology that is encapsulated in the Central Dogma. We call this view molecular genetics.
One of the central challenges for a student of genetics is that both of these definitions are "correct." One of the goals of this course is for you to develop your ability to connect these two views, to jump between them as necessary, and to see how they both inform the way we use genetics as a tool to study living systems.
Before we jump in, though, let's review what you should have learned about both transmission genetics and molecular genetics from your introductory courses. We'll also introduce some ideas from probability and statistics that we'll be using regularly this semester.
Figure \(\PageIndex{1}\): Gregor Mendel. (Copyright Pelycosaur24@DeviantArt, CC BY-NC-ND)