Nova: Cracking your Genetic Code
Integrated Science 2
Name:
Pd.
1. Sequencing the first human genome took ___________ years, three billion dollars, and hundreds of scientists.
The first draft was finished in _______________.
2. Your genome is a language whose alphabet consists of four chemicals, each known by its initial
__________________________. Strings of these chemical letters spell out some 20,000 genes on 23 pairs of
chromosomes. Genes code for proteins, molecules that do most of the work in our cells and help _______________
parts of our body, from muscles to hair.
3. What is the name of the Silicon Valley start-up company that offers a genome scan? What does the “23”
represent?
4. Human genomes are ___________ percent identical. By analyzing your spit, 23andMe will show you a million
sites in your genes where the spelling sometimes differs between people. These one-letter variants may predispose
you to certain traits and diseases. A million letters is less than ______________ percent of your DNA.
5. What is one of the “odd traits” that genotyping can explain?
6. Variants of genes are going to work together with your ________________. They’re not guaranteeing anything.
It depends on how you eat, do your exercise.
7. Which “one gene” did James Watson, the man who co-discovered the double helix of DNA, not want to “know
anything about”? What was the increase in risk for those that had the gene?
8. Some genes speak louder than others. Although we get two copies of most genes, one from each parent, certain
dominant genes confer a _______________ of their own. And certain dominant disease genes, although rare, will
eventually make you ______________.
9. Catherine Elton found a disease-causing variant of a gene called BRCA1 that is considered “actionable” (you can
do something about it if you know about it). What does it cause and how might knowing you have it help you?
10. So far, scientists have found about ______________ “actionable” genes.
11. In the video, Andrew had his genome decoded by a company called Illumina. How long did it take and how
much did it cost?
12. The CFTR gene on chromosome 7 can cause Cystic Fibrosis if there is a mutation. How many different
mutations can cause Cystic Fibrosis?
13. Explain Cystic Fibrosis
14. Sequencing a cancer is as big as the human genome. Each cancer cell has an entire human genome in it, just
____________________ in various ways.
15. How does the BRAF medicine stop melanoma cancer?
16. Cancer cells, like viruses and bacteria, can evolve to _____________ drugs. But now the ability to compare
cancer genomes before and after treatment is allowing scientists to see how resistance develops. With resistance,
new _____________________ arise in melanoma tumors, and once again defective proteins ignite the cancer.
17. By fertilizing an egg and producing an __________ cell embryo, you can pluck off one of those cells and
analyze its genes. Then you can screen that embryo for a host of diseases, using a technique called “preimplantation
_________________ diagnosis” or PGD.
18. At the Genesis Genetics Institute, Mark Hughes and his team are using PGD to test embryos for mutations that
can give ruse to over _________________ diseases, including Huntington’s and cystic fibrosis. Only embryos free
of certain mutations are implanted in the mother.
19. Why is it likely that we won’t be able to select for traits that a “genetic elite” would want?
20. Explain “genomic hacking” and how it can be dangerous.
Post-Video Analysis
1. You send your DNA to “23 and Me” and you learn you have a 20% higher chance of heart disease than the
average individual. Would you make changes to your eating habits, exercise habits, behavior, etc? Explain why or
why not.
2. Your family has learned that your mother has Huntington’s Disease. As a 14-15 year old teenager, would you
get the test to find out if you have the genotype for Huntington’s? Would you do so later in life? Explain.
3. It is the year 2030 and you and your spouse are planning on having a baby. Technology allows you to fertilize
multiple eggs and select for characteristics like gender, height, facial beauty, intelligence, and happiness. Do you
take advantage of this technology and, if so, what type of child do you select? Explain your answer either way.