Karina Makarova – Biology 9
The Life of a Gene in a Chromosomal Mutation
It all started with me, a tiny little gene, along with hundreds of my other gene friends inside the body of a
beautiful girl, Sally. She was just a fetus back then, a small egg, arriving into her mother’s stomach. Every
day we went around doing what all genes are supposed to do, slowly living through each step of Sally’s
growth. It was great to finally work, until a single day changed everything.
I was out and about with Greg, my best gene, and there was all of a sudden a loud sound. We ran back to
our stations (mine being on chromosome 5, near the short arm) and I noticed Bob (the chromosome)
acting rather strange as he was lining up for the
metaphase. Everybody went chaotic, until the room
went dead silent. I closed my eyes and realized,
remembering what I had learned at GeneSchool, that
because of poor Bob, most of the short arm and the
genes on it would be deleted! The DNA molecule that
was still helping form Sally, was slowly breaking and
wouldn’t make Bob’s short arm a healthy part of the
chromosome. Opening my eyes, the room slowly went
blank and we all disappeared.
I wasn’t upset at first, knowing that it’s just the way it is,
but Sally would never be the same… a few missing genes and a huge part of a chromosome, containing
over 181 million DNA building blocks are enough to alter the whole growing process and create a
syndrome for her with the name of Cri-Du-Chat.
Once the leftover chromosomes learn how to adapt to this syndrome, Sally will have unusual facial
features, cat-like cries, heart defects, speech problems, and more. Though her life will change quite a bit,
she’ll be like the rest of the kids by the age of two and outgrow any obstacles thrown at her.
1) Before writing my story, there was quite a lot I needed to research and know. I started off finding
out what my syndrome was, the problem that occurred causing it, and what it does to the human.
I then looked at different treatments (sadly to find there aren’t any) and if the effect on the human
was positive, negative, or neutral.
Here are the questions and answers:

What happened to the chromosome and genes?
The short arm of chromosome 5 got deleted, along with all the genes located on it. The deletion occurred
at the Metaphase Stage of meiosis because the chromatins weren’t properly lined up.
Karina Makarova – Biology 9

What caused the deletion?
It was caused by a break in the DNA molecule, which should make up
a chromosome. This happens during the development of a sperm or
egg cell.

What are the effects on the human after genetic
mutation/how is the human’s life affected?
The biggest symptom of cri-du-chat is the child’s respiratory
problems, which causes them to have a “cat-like cry”. Other effects
include feeding difficulties (swallowing and sucking), low weight,
severe speech delays, unusual facial features, excessive drooling, and
a small head. Small amounts of children even have several problems
inside of their bodies, such as heart defects, muscular/skeletal
problems, hearing and sight deficiencies, and problems with walking/
talking.

What was the genetic mutation (positive, negative, etc.)?
The mutation, because of all the health problems and symptoms, would be negative.

Can this syndrome be treated?
There isn’t any specific treatment for Cri-du-Chat, but if the child has language disability, it is possible for
them to go into speech therapy to improve their speaking skills. In some cases though, by the time the
child is 2 years of age, the syndrome can almost disappear and not be as noticeable (as it is when they’re
younger).
2) My most used digital tool was Google, but when getting more into those searched sites, I actually
found webpages located at the bottom of each site, blogs, and YouTube videos. As I read the new
information I found, it helped me a lot with a number of blanks in my research.
http://learn.genetics.utah.edu/content/disorders/chromosomal/cdc/
https://www.genome.gov/19517558
https://youtu.be/39KmzaXJenA
https://youtu.be/lgIx-_SU9GE
https://en.wikipedia.org/wiki/Cri_du_chat
Karina Makarova – Biology 9
3) The process I used to investigate was by just learning everything there was on my syndrome, and
if I still wasn’t sure, I specifically googled what I didn’t understand (or asked Ms. Lundgren).
4) I verified the cite information by scrolling down the page to see who posted, it was usually either
a hospital or a professional biology teacher.
5) The process went pretty well, I learned much more by completing this assignment and without it,
I would probably easily forget everything until we learn it again next year. What I could’ve done
better is researching completely what a chromosome and gene are, instead of writing my story of
what I thought they were and then rewriting it later on with the actual definitions in mind. That
would’ve cut down all the time I spent on this assignment by a lot!