miniPCR bio
TM
Chopped! Using CRISPR/Cas9 to cut DNA - Student's Guide
Version: 1.0 - Release: May 2022 - © 2022 by miniPCR bio™
Student's Guide
P./33
5. Now, calculate about how many times you would expect the Cas9 enzyme to find and cut
a specific 20-base-pair sequence in the 3.2 billion (3,200,000,000) base pair-long human
genome. You should use a calculator, but show your work.
6. Your answer to the previous question should be a number that is less than 1. This tells us
that it is not likely for that specific 20-base sequence to appear even once in the 3.2 billion
(3,200,000,000) base-pair sequence. This means that any 20-base sequence within the
human genome will likely only appear once, if at all. Explain why this makes the CRISPR/
Cas9 system a good genome editing tool.
