Written by Kelly A. Hogan, University of North Carolina at Chapel Hill

The genetic code is often described as being analogous to the written language. I expand this analogy to help students understand the hierarchy that exists in genetics, since I find many students don’t understand the relationship between a gene and a chromosome. Imagine a set of books, perhaps the Harry Potter series. The entire series on the shelf is analogous to the genome. Each book can be thought of as a chromosome. Within each book are chapters, these can be thought of as genes. Lastly, the 26 letters of the alphabet are arranged to make the variation of words within the genes. The genetic code has 4 letters to make unique arrangements/sequences. What would be the consequence if a few sentences or a chapter or an entire book was lost from the series? Would the story still make sense? (This would be analogous to mutations and chromosomal abnormalities.)