CAT TAG
It’s February. The month of love. The perfect month to declare my love of genetics to the STEM Tuesday world in the passionate execution of my Week 3 Writing Craft & Resources post. I love genetics!
It is more than mere fate or blind luck that the STEM Tuesday schedule and my posting schedule aligned for February 2023. The STEM nonfiction universe knows.
Genetics + Me = #ForLife.
But what does all that have to do with a Writing Craft & Resources post? Bear with me, please, through my soliloquy on genetics.
Genetics had me at my first Punnett square. Just like Mendel and his pea plants or Barbara McClintock and her corn chromosomes, genetics had me hooked from the get-go. The idea that life has a blueprint and we have the ability to study and define it captured the teenage me as much as sports had. As a son of a civil engineer who designed and built bridges and highways, plus, as someone just getting into computer programming on my Texas Instruments TI-99, I was hooked on the coded blueprint of life for life.
Then deoxyribonucleic acid came along. The fundamental code of life. Adenine (A), cytosine (C), guanine (G), and thymine (T). Four chemical bases attach to a sugar-phosphate backbone to form a nucleotide. Four bases that pair with one another (A-T and C-G) in a particular order to form a double-helix strand of DNA and the chromosome. Just about everything we see in the living world is built from the order of those four bases. A, T, C, and G, coded in the chromosome blueprint.
The genetic information coded in our DNA is transcribed into a specific protein in the central dogma of genetics, DNA→RNA→Protein. The triplet code is the key to the central dogma during the transcription of the DNA code. The cell’s machinery reads the code three nucleotide bases at a time and makes RNA copies of them which, in turn, code for one of 20 amino acids used to construct a protein.
Humans have about 38 trillion cells in the body and each of those cells contains the code for ~20,000 genes within its chromosomes. The total length of the DNA in one cell is six feet. That’s a lot of DNA needing to be intricately folded to fit inside the cell’s nucleus! Each cell transcribes the proper genes at the proper time to make the proper proteins it needs to function. The cell must keep the genetic code organized while maintaining its integrity and repairing any damage to the code. Add to that, the need to faithfully replicates itself for future progeny cells so mistakes in the code, called mutations, don’t get passed to the next generation of cells.
This molecular dance of life. with its high level of fidelity. never ceases to blow my mind.
I’ve made a career chasing DNA. I’ve cloned it and I’ve sequenced it. I’ve digested, purified, manipulated, mutated, labeled, edited, and analyzed it. Everything I’ve done in three decades of science revolves around A, T, C, and G. And even after all this time, there is still so much that I don’t know about genetics and DNA and the molecular dance of life, which brings me back to writing.
Everybody knows writing is work. It’s hard work but, similar to genetics, it is also work that has me hooked. Also like genetics, there’s is still so much I need to learn about writing, even after decades of writing. Just as there are the tools of genetics, writers have tools. Letters, words, structure, and grammar are the nucleotide bases (A/T/C/G), genes, chromosomes, and triplet code of genetics.
Word→Sentence→Paragraph is the writer’s central dogma. Finding the right words to describe our ideas and transcribing them in legible form is what we attempt to do as writers.
When I teach what we do in our lab or speak to students about genetics and genetic mutations, I use a little paper demonstration called CAT TAG. It’s based on transcription using the triplet code defined above. I use it to describe how important it is to preserve the correct sequence and fidelity of the triplet code when we are cloning or mutating a gene for further analysis.
Here’s the imaginary DNA code sequence I use for the CAT TAG gene demonstration:
ATG CAT TAG CAT TAG CAT TAG CAT TAG
If we start transcribing at the “ATG” start codon signal, we get frolicking felines playing an adorable game of CAT TAG protein.
CAT TAG CAT TAG CAT TAG CAT TAG
What happens when we inadvertently insert a base in the gene?
ATG tCAT TAG CAT TAG CAT TAG CAT TAG
We get nonsense and no more frolicking feline protein. Where did my adorable cats go!!!
tCA TTA GCA TTA GCA TTA GCA TTA G
The same thing happens when we delete a base in the gene. Nonsense and no cats!
ATG AT TAG CAT TAG CAT TAG CAT TAG
ATT AGC ATT AGC ATT AGC ATT AG
Even more frightful, what if a whole CAT codon gets deleted?
ATG TAG CAT TAG CAT TAG CAT TAG
Argghh!!!!! Ouch!!! Now I’m tagging the cat and the cat does not appreciate it! Ouch!
TAG CAT TAG CAT TAG CAT TAG
Writing is like the CAT TAG gene game. Finding the right order and sequence of words to express ideas is the ultimate goal. The skill and magic of revision lie not only in the order and sequence but in finding the best words to express the idea. No more or no less. Make sure additions or subtractions fit properly.
The goal is to find the adorable cats playing tag version of your writing without creating confusion, nonsense, or attacking felines.
Mike Hays has worked hard from a young age to be a well-rounded individual. A well-rounded, equal-opportunity sports enthusiast, that is. If they keep a score, he’ll either watch it, play it, or coach it. A molecular microbiologist by day, middle-grade author, sports coach, and general good citizen by night, he blogs about sports/training-related topics at www.coachhays.com and writer stuff at www.mikehaysbooks.com. Two of his science essays, The Science of Jurassic Park and Zombie Microbiology 101, are included in the Putting the Science in Fiction collection from Writer’s Digest Books. He can be found roaming around the Twitter-sphere under the guise of @coachhays64 and on Instagram at @mikehays64.
The O.O.L.F Files
This month’s version of the O.O.L.F.(Out of Left Field) Files explores revision tips, genetics history with two of the faces on the Mount Rushmore of genetics, a lesson in genetic expression, and CRISPR gene editing at home.
Kirsten W. Larson’s Revision Tip: Unwriting Your Draft blog post
Barbara McClintock
- Barbara McClintock and the Discovery of Jumping Genes (Transposons)
- Profiles in Science – Barbara McClintock (1902-1992)
Gregor Mendel
The fabulous Punnett square
University of Nebraska-Lincoln Plant & Soil Science Learning Module
Janet Slingerland is the author of over 20 books for young readers. Her latest project involves increasing the biodiversity in her yard by planting a wide variety of native plants. To find out more about Janet and her books, check out 
