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NOVA scienceNOW: Personal DNA Testing

Program Overview

Scientists describe the revealing information that a personal genetic profile provides and discuss the questions and issues people face once this highly personal information is available.

This NOVA scienceNOW segment:

  • describes a company that analyzes DNA and provides clients with information about their risk factors for specific diseases.

  • reviews the structure of DNA and tells how DNA samples are obtained.

  • explains that most human DNA is identical across all people, but differences exist—between individuals, about three million base pairs out of six billion are different (one-twentieth of a percent). This genetic variation makes us unique, but it's also what predisposes us to genetic diseases.

  • terms each spot in the DNA where a single base is different as a Single Nucleotide Polymorphism (SNP).

  • introduces SNP ("snip") chips—silicon chips that hold millions of small fragments of reference DNA.

  • reports that SNP chips enable one to compare an individual's SNP profile to those of people with specific genetic diseases.

  • explains that most diseases involve the interaction of many genes and the environment, so genetic testing does not conclusively predict whether one will get a specific disease.

  • points out that some physicians question the value of this type of genetic testing and even believe it may be hurtful, because knowing about a disease predisposition may cause some people to become depressed or possibly even commit suicide.

  • states that the greatest challenge of the genetic revolution may be how we cope with personal information that is revealing yet uncertain.

Taping Rights: Can be used up to one year after the program is taped off the air.

Teacher's Guide
NOVA scienceNOW: Personal DNA Testing

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