NOVA Online (see text links below)
Cracking the Code of Life
Watch The Program - Teachers
This two-hour program is divided into 16 chapters. Choose any chapter below and select QuickTime or Real Video to begin viewing. If you experience difficulty viewing, it may be due to high demand. We regret this, and suggest you try back at another time. Due to rights restrictions this program is not available for downloading.

Feedback | Technical Help | Program Credits | Program Transcript
Advanced options | Watch other NOVA programs online

Chapter 1
1. Instructions for a Human Being

This chapter:
  • previews the program's focus on the race to decode the human genome and raises some of the scientific and social ramifications involved.
  • notes that scientists have worked 10 years to read the entire human genome.
  • explains that DNA is a chemical message that began more than four billion years ago with the first signs of life on Earth.
  • describes the ladder-like structure and chemical makeup of DNA.
running time 09:06

watch it in
QuickTime | RealVideo

Chapter 2
2. Getting the Letters Out

This chapter:
  • notes that every human baby born is 99.5 percent identical to every other baby.
  • explains that the Human Genome Project is devoted to decoding and understanding the small percentage of differences among humans.
  • recalls that in the project's earliest days, reading the DNA code was a timely and arduous process, allowing only a few hundred letters to be hand-read each day.
  • states that by using computers, the process was sped up to reading a thousand letters a second.
  • reviews some metaphors used to describe the decoding of all three billion letters in the human genome.
running time 05:52

watch it in
QuickTime | RealVideo

Chapter 3
3. One Wrong Letter

This chapter:
  • describes parents Allison and Tim Lord, whose two-year-old son, Hayden, was diagnosed with Tay-Sachs, an incurable degenerative brain disease.
  • explains that Tay-Sachs is a one-letter mutation in the genome that causes the gene it's on to create a faulty protein—one that is unable to dissolve fat in the brain.
  • relates that Tim's brother, Charlie, and his wife, Blyth, have also been affected by Tay-Sachs. Of their two children, one is a carrier and the other has the disease.
  • notes that Tay-Sachs usually occurs in specific groups, like Ashkenazi Jews, and must be inherited from both parents.
  • states that the Human Genome Project offers the potential for people to find out early if they are at risk for a disease, or for passing on a disease to their children.
running time 08:57

watch it in
QuickTime | RealVideo

Chapter 4
4. The Sequencing Race Begins

This chapter:
  • notes that first and foremost, the promise of the Human Genome Project is to allow for an early warning system for a host of diseases.
  • introduces Craig Venter, the scientist who started Celera Genomics, a private company devoted to decoding the human genome using a more efficient, automated process than employed by most public labs at the time.
  • explains how the automated DNA-reading process works.
  • profiles Venter's background.
  • reports Venter's 1998 announcement that he and his company were going to sequence all 3 billion letters of the human genome in two years, a process the government estimated would take 15 years.
running time 06:29

watch it in
QuickTime | RealVideo

Chapter 5
5. Ramping up

This chapter:
  • recalls how everyone working on the public human genome project raced to find ways to speed up their efforts in response to Venter's announcement.
  • notes that the public centers, which found ways to accelerate sequencing, would nightly post their latest data on the Internet.
  • reports that Celera used the Internet data posted by the labs.
  • raises the question of why the government should fund research duplicating that done by Celera.
running time 07:48

watch it in
QuickTime | RealVideo

Chapter 6
6. Genetic Variation

This chapter:
  • reviews how both the public labs and Celera chose volunteers to submit DNA for mapping.
  • reports that human beings are incredibly similar in genetic makeup, varying only about one tenth of a percent, less than chimpanzees, whose average difference is four to five times more than the difference between any two humans.
  • states that the small differences in human's genetic makeup results from homo sapiens being such a young species and descending from a very small founding population.
  • notes the similarities in DNA between humans and all other living things, from bananas to baker's yeast.
running time 06:33

watch it in
QuickTime | RealVideo

Chapter 7
7. Who Owns the Genome?

This chapter:
  • notes that the drive to complete the decoding process was partly motivated by the fact that some people were trying to privatize the human genome by patenting human genes they had decoded.
  • reviews some arguments for and against patenting genetic code.
  • states that there are 20,000 genetic patents under review in the U.S. Patent Office.
  • presents the effects of patenting on current research efforts.
running time 07:52

watch it in
QuickTime | RealVideo

Chapter 8
8. The Business of Science

This chapter:
  • looks at the role of business in scientific advancement.
  • describes Celera's main source of income—its fee-based Web site that includes information on the genomes of several species, including fruit flies, mice, and humans.
  • notes how Celera's business model conflicts with the traditional way science is done, which results are publicly shared with others who can then freely build on those results.
running time 04:06

watch it in
QuickTime | RealVideo

Chapter 9
9. Finding Cures is Hard

This chapter:
  • notes that it takes much more than knowing the sequence of DNA to find cures for disease.
  • profiles Rily Demanche, an infant diagnosed with cystic fibrosis (CF), a disease that causes chronic respiratory infections.
  • reports that while the genetic defect for CF—a three-letter error—was discovered in 1989, attempts at gene therapy have been unsuccessful to date.
  • states that scientists are now looking at ways to repair the proteins involved in CF.
  • notes that proteins and protein activities are what physically compose a human being.
  • relates that while genes are effectively a one-dimensional string of letters, proteins are three dimensional.
  • describes how a gene codes for an amino acid sequence that forms a protein, which then forms a shape that defines its task.
  • specifies how the misshapen protein involved with CF prevents salt from leaving the lung cells, thus triggering a chain of reactions that causes the cell to become covered with thick mucus, which must then be physically dislodged.
running time 08:07

watch it in
QuickTime | RealVideo

Chapter 10
10. Complexity in Proteins

This chapter:
  • presents the case of Tony Raimos, a patient who, though diagnosed with CF, did not develop symptoms until she was 15 years old.
  • relates the theory that Raimos may have other genetic mutations that have kept her more healthy than most CF patients.
  • introduces the search for the proteome—all the proteins that make up a human being—as one of the next steps involved in understanding life at the molecular level.
  • notes that while researchers believed humans had about 100,000 genes, they discovered only about 30,000 .
  • reports that while humans only have about twice as many genes as a fruit fly, human genes seem to code for much more complex proteins.
running time 07:44

watch it in
QuickTime | RealVideo

Chapter 11
11. The Finish Line

This chapter:
  • continues to track the race to decode the human genome.
  • notes the atmosphere in Celera's labs in the final stretch of the decoding race.
  • cites some of Venter's reasons for wanting to decode the genome as quickly as possible.
running time 04:32

watch it in
QuickTime | RealVideo

Chapter 12
12. Finding Disease Genes

This chapter:
  • explains how having the genome decoded should make it easier to find causes for disease.
  • steps through the process of how scientists might help pinpoint which genes are responsible for which traits.
  • showcases Iceland's database of almost every citizen's family tree as a way to compare genetic histories and identify diseases.
  • follows Kari Stefansson, a scientist who set up DeCODE Genetics in order to combine Iceland's genetic histories with DNA analysis to pinpoint genetic diseases.
  • profiles the case of Regnheidir Magnusdottir, one of 11 out of 17 children in a family stricken with osteoarthritis.
  • recounts how Stefansson offered a fee and profits to the Icelandic government in return for exclusive access to the country's medical records, and how the government and population of Iceland responded to the request.
running time 04:06

watch it in
QuickTime | RealVideo

Chapter 13
13. DNA Databases

This chapter:
  • reviews some of the ethical issues surrounding the creation of DNA databases.

    * presents film clips from the movie GATTACA.
  • explains how DNA chips would allow doctors to screen babies for numerous diseases and discusses some of the implications of this type of information.
running time 04:14

watch it in
QuickTime | RealVideo

Chapter 14
14. A Family Disease

This chapter:
  • profiles Lissa Kapust and Lori Siegel, older sisters to youngest sister, Melanie, who died of ovarian cancer when she was 30 years old.
  • describes Lissa being treated for breast cancer when she was 34 and again in 1996, about the time scientists were determining a familial link between breast and ovarian cancers.
  • reviews the mutations in two genes—BRCA 1 and 2 - which significantly increase one's risk of developing cancer.
  • follows Lissa and Lori as doctors test both for the presence of the mutated genes, and raises the question of what having such a test might mean.
running time 08:05

watch it in
QuickTime | RealVideo

Chapter 15
15. Genetic Modification

This chapter:
  • presents a movie clip from GATTACA that illustrates the idea of genetic enhancement of unborn children.
  • explores how far humans may be able to go with genetic manipulation.
running time 04:27

watch it in
QuickTime | RealVideo

Chapter 16
16. Contemplating the Message

This chapter:
  • revisits issues arising from the privatization of decoding the human genome.
  • presents Celera and the public project scientists agreeing to share the credit for sequencing the genome.
  • explores the idea that the genome is very uneven—that is, that the 30,000 genes are not evenly distributed across the chromosomes.
  • concludes with the idea that while humans are similar to every other living thing on Earth, something extraordinary exists that makes them very different.
running time 07:58

watch it in
QuickTime | RealVideo

Feedback | Technical Help | Program Credits
Advanced options | Watch other NOVA programs online

Watch the Program Here | Our Genetic Future (A Survey)
Manipulating Genes: How Much is Too Much? | Understanding Heredity
Explore a Stretch of Code | Nature vs Nurture Revisited
Sequence for Yourself | Journey into DNA | Meet the Decoders
Resources | Update to Program | Teacher's Guide | Transcript
Site Map | Cracking the Code of Life Home

Editor's Picks | Previous Sites | Join Us/E-mail | TV/Web Schedule | About NOVA
Watch NOVAs online | Teachers | Site Map | Shop | Search | To Print
PBS Online | NOVA Online | WGBH

© | Updated April 2001
/wgbh/nova/genome/textindex.html /wgbh/nova/genome/