MODERN GENETICS USES DNA TECHNOLOGY

• CHANGES IN DNA CAN CHANGE AN ORGANISM (via selective breeding and genetic engineering) – Random DNA changes may introduce new traits into an

organism. Over time certain traits may be more common in 1 group as they interact with environment.

• THERE ARE RISKS & BENEFITS ASSOCIATED WITH GENETIC ENGINEERING

• DNA TECHNOLOGY HAS MANY APPLICATIONS (through DNA identification and Studying Genomes).

DNA CHANGES CHANGING AN ORGANISM

• SELECTIVE BREEDING: selecting and breeding parent organisms to pass on particular traits to offspring.

• People were not changing DNA, just letting certain alleles become more common in a particular breed.

• Different breeds of dogs show this.

CHANGING ORGANISMS

• Genetic Engineering: a sequence of DNA from an organism is isolated, changed, & returned to an organism or another organism. (can take gene from one species and transfer it into DNA of another). The resulting organism is genetically modified or (GM).

• Genetically modified plants have insect-resistant genes from micro-organisms spliced into their DNA, protecting them from bugs.

• Genetically modified tomatoes are now able to grow in very salty soil like the cabbage they received a gene from.

Risks & Benefits with Genetic Engineering

• Most everyone has eaten GM corn/soybeans. They are insect resistant, so increases food production, and less chemical pesticides needed, so less environmental pollution.

• Many worry of possible effects on humans. Also, what if they cross-breed so weeds grow out of control.

• Scientists try to keep genetically modified plants and animals out of the general population in case it would have a negative effect on the natural wild population. Much debate continues dealing with this issue.

DNA TECHNOLOGY HAS MANY USES

• DNA technology can be used to add nutrients to food, make new & better drugs, see if a drug might cause side effects, screen for and maybe treat genetic disorders.

• Law enforcement uses DNA fingerprinting (unique unless identical twin) to solve crimes. The more matches between crime scene DNA and suspect’s DNA, the higher the probability suspect is guilty.

• Experts recommend 4-6 DNA regions be matched to establish guilt (chances are very small someone else would have the same DNA for this number of regions).

DNA technology• GENOME: all the genetic material

in an organism. • HUMAN GENOME PROJECT:

tried to sequence the 3 billion nucleotide pairs in a single set of human chromosomes. First sequence finished in 2001, now scientists working to identify the 30,000 genes found

• We as a society have to decide when it is acceptable to change DNA & how to use the technology we have.

DNA technology continued

• CLONING: a technique using technology to make copies of DNA. Can be used for a segment of DNA or an entire organism.

• Cloning has been used with bacteria to make protein & drugs to help fight disease (human insulin from GM bacteria cloned)

• First mammal cloned in 1996, Dolly the sheep.• Ability to clone such a complex animal raises

many concerns about the future use of cloning.