Additional DNA Technology AP Biology Ms. Day Biotechnology (Part 3) Additional DNA Technology AP Biology Ms. Day

After genes are cloned… A genomic library is made using bacteriophages (virsues) or bacteria A stored as a collection of phage clones or bacteria clones

Storing Cloned Genes in DNA Libraries Figure 20.6 Foreign genome cut up with restriction enzyme Recombinant plasmids Recombinant phage DNA Phage clones (b) Phage library (a) Plasmid library or Bacterial clones

Made when cloning a eukaryotic gene of interest INTO a prokaryote Complementary DNA (cDNA) Made when cloning a eukaryotic gene of interest INTO a prokaryote Uses reverse transcription of all the mRNA produced by a particular cell http://highered.mcgraw-hill.com/sites/0072437316/student_view0/chapter16/animations.html#

What if a scientist need A LOT of DNA copies? Use the polymerase chain reaction, PCR Produces many copies of a specific target segment of DNA Uses DNA primers (pieces) that bracket the desired sequence Uses a heat-resistant DNA polymerase

DNA Amplification  makes a lot of DNA copies PCR = polymerase chain reaction PCR Animation http://highered.mcgraw-hill.com/sites/0072437316/student_view0/chapter16/animations.html# Animation #9

Restriction Fragment Analysis detects DNA differences that affect restriction sites Restriction fragment analysis provides useful comparative information about DNA sequences

http://www. sumanasinc http://www.sumanasinc.com/webcontent/animations/content/gelelectrophoresis.html

Restriction Fragment Analysis Figure 20.9a, b Normal  -globin allele Sickle-cell mutant -globin allele 175 bp 201 bp Large fragment DdeI 376 bp DdeI restriction sites in normal and sickle-cell alleles of -globin gene. Electrophoresis of restriction fragments from normal and sickle-cell alleles. Normal allele Sickle-cell allele 201 bp 175 bp (a) (b) Is useful for comparing two different DNA molecules, such as two alleles for a gene http://highered.mcgraw-hill.com/sites/0072437316/student_view0/chapter16/animations.html#

Restriction Fragment Length Differences as Genetic Markers Restriction fragment length polymorphisms (RFLPs) Are differences in DNA sequences on homologous chromosomes result in DIFFERENT restriction fragments lengths

Think… In your groups, come up with 4 ways in which biotechnology is used in 2017.

Current Uses for Biotechnology: 1.) Medical Applications identification of MUTATED human genes that plays a role in genetic diseases Medical scientists can now diagnose hundreds of human genetic disorders

Human Gene Therapy Gene therapy When you alter an individual’s MUTATED genes Holds great potential for treating disorders traceable to a single defective gene Uses various vectors for delivery of genes into cells (plasmids, vectors, etc)

Gene therapy using a retroviral vector Let retrovirus infect bone marrow cells that have been removed from the patient and cultured. 2 Viral DNA carrying the normal allele inserts into chromosome. 3 Inject engineered cells into patient. 4

2. Pharmaceutical Applications Applications of DNA technology include Large-scale production of human hormones and other proteins with therapeutic uses (ex: insulin) Production of safer vaccines

3. Forensic Applications DNA “fingerprints” obtained by analysis of tissue or body fluids found at crime scenes Can provide criminal evidence Establish paternity/maternity

4. Environmental Applications Genetic engineering can be used to modify the metabolism of microorganisms Some microorganisms can “eat” minerals (ex: oil) from environment or degrade toxic waste materials

5. Agricultural Applications DNA technology Is being used to improve agricultural productivity and food quality

6. Pharming and GMO’s Transgenic animals and GMO’s Contain genes from other organisms https://www.youtube.com/watch?v=kLzjXQX4EMQ Transgenic Video (Chapter 20) http://www.dnatube.com/video/204/Creation-of-a-Transgenic-Animal