Recombinant DNA and CloningThe Impact of Biotechnology

Honors Genetics

Ms. Susan Chabot

Lemon Bay High School

Terms to Know

• Restriction enzymes: allow the DNA to be cut and spliced at VERY specific locations.

• Vectors: carriers of DNA molecules; usually bacteria.

• Plasmid: circular DNA found in bacteria.

• Recombinant DNA: original carrier DNA + introduced sections of DNA.

• Clones: when the bacteria divide, millions of copies of the original recombinant DNA are made.

Impact of Biotechnology• Biotechnology: use of modified organisms or their

products to enhance our lives.• Ethical Dilemmas:

– Patenting genes for ownership.• Patents offer scientists a chance to fund further research.

– Limited availability of seeds to farmers.• Concentrates crop ownership to biotech companies, out of farmer’s

hands.

– Impact of GM foods in our own bodies.• Enough testing to identify risks/benefits?

• Biotech and Medicine:– Too much information too early?– Inability to get medical insurance.

Figure 24.1

Genetically Engineered Organisms Synthesize a Wide Range of Biological and Pharmaceutical Products

Genetically Modified Plants

• Resistance to insects, weeds, and viruses.

• Enhanced oil content.• Delayed ripening.

• GM foods can also be modified to increase the nutritional content of foods.– GM rice (golden rice) has

been modified to contain more of the building blocks needed to produce Vitamin A.

– Reduced blindness in poorer nations.

• Over a dozen genetically modified crops approved to grow in the US.– 45% of US corn crop.

– 85% of soybean crop.

• 60% of processed food contains GM foods.

GM Animals• Embryo splitting has

created commercially cloned GM organisms for 25 years.

• Don’t have to wait until adulthood to see if desired traits were inherited.

• Cloned for desirable traits such as:– High milk production.

– Speed in race horses.

– Transgenic animals.

• Transgenic animals are produced when one animal’s desired traits are recombined into another animal.– Human genes

transferred into sheep for production of human proteins.

Table 24.1

Figure 24.2

Recombinant DNA Approaches for Vaccine Production and Transgenic Plants with Edible Vaccines

During the past 10 year s, transgenic crops have been rapidly adopted in both industrialized and developing countries.

Roundup-Ready GM soybeans

1. Gene for enzyme embedded into plasmid.

2. Plasmid inserted into bacteria.

3. Bacteria inserts plasmid into plant nucleus.

4. The gene for the enzyme is inserted into the plant chromosome.

5. The gene is expressed and the plant will be resistant to the herbicide Roundup.

GM Roundup resistant soybean plants. Allows Roundup to be applied to the crop to kill weeds but not harm the soybean.

Golden Rice•genetically modified to produce -carotene, a precursor to vitamin A.•Many children in countries where rice is a dietary staple lose their eyesight because of diets deficient in vitamin A.

Transgenic Atlantic salmon (bottom) overexpressing a growth hormone (GH) gene .

GloFish, marketed as the world’s first GM-pet

Chorionic villi Sampling: Performed at 10 -12 weeks.

Genetic Engineering and Genomics Are Transforming Medical Diagnosis

Genetic Engineering and Genomics Are Transforming Medical DiagnosisPerformed at 14 – 20 weeks

Needle is inserted through the abdominal and uterine walls to recover amniotic fluid and fetal cells for genetic or biochemical analysis.

A single cell from an early-stage human embryo created by in vitro fertilization can be removed and subjected to pre-implantation genetic diagnosis (PGD).

Text Reading

• On own, read Model Organisms to understand how genetics can be studied through the use of model organisms.

• What are examples of Model Organisms?• What makes a good Model Organism?

Chapter 1 Essential Points• Page 4: #1: Mendel’s Work.• Page 5: #2: Chromosome Theory of Inheritance• Page 8: #3: Central Dogma of Biology• Page 12: #4: Biotech has revolutionized agriculture and

pharmaceutical industries. Genetic testing and gene therapy has impacted how we treat and diagnose genetic diseases.

#5: Recombinant DNA technology has given rise to several new fields in science.

• Page 14: #6: Using model organisms allows us to use genetics and biotech to understand human health.

#7: Policies and regulations that pertain to genetic technology is lagging behind the technologies that are being introduced.