DNA Tools & Biotechnology

Question 1

Restriction Endonuclease

Answer 1

(R.E.), late 1960’s, isolated in bacteria.
1. Function: Protection from foreign DNA
2. Cut foreign DNA at gene of interest
3. Leaves “sticky ends” or blunt ends, DNA ligase seals.
4. Hundreds of different R.E. known, named based on Genus-Species-Strain-#
5. Allows creation of recombinant molecules in test tube
6. Beginning of ‘molecular genetics’

Question 2

DNA libraries

Answer 2

Collections of dif. recombinant molecules typically in a host cell (E. coli). Genomic DNA library- has copies of all genes from a genome.

Question 3

cDNA library

Answer 3

Smaller than Genomic DNA library, easier to find a specific genome. (complementary DNA). Made from a specific tissue.

Question 4

Gel electrophoeresis

Answer 4

Separates molecules based on charge & size. If molecules have same charge/mass ratio (DNA), then molecules only separated based on size.

Question 5

Amplification of DNA (or RNA)

Answer 5

Fast, only works with a small region of interest. PCR (Polymerase Chain Reaction). Discovered: 1983, Kary Mullis. Produces lots of DNA from a small segment of DNA. RT-PCR - Reverse transcriptase-polymerase chain reaction.

Question 6

DNA sequencing

Answer 6

Can be done manually since 1980, around 1000 nucleotide pairs/day. Nowadays, 900 million nucleotides in 10 hours.

Question 7

Stem cell

Answer 7

Unspecialized cell that can renew itself and can produce cells that can differentiate into specialized cells of one or more types.
1. Totipotent: a stem cell that can give rise to all cells of an organism
2. Pluripotent: a stem cell that can give rise to most cells of an organism.
3. Multipotent: a stem cell that can give rise to several different cells.

Question 8

GEM’s

Answer 8

Genetically engineered microbes. Produce rare/expensive human hormones, neurotransmitters, etc.
i.e. Insulin: treat some types of diabetes.
Interferon: useful for antiviral properties
a. 20,000 pints of blood yield 20-40 mg, $10,000. 1 liter GEM yield 20-40 mg, $10.

Question 9

Pharmaceutical factories

Answer 9

‘Pharm’ animal production of large quantities of protein products.

Question 10

STRs and RFLPs

Answer 10

a. Short tandem repeats: highly variable from person to person.
b. Restriction fragment length polymorphism: length varies.
Useful for forensics.

Question 11

Eugenics

Answer 11

Study of how to arrange reproduction w/in a human pop, to increase the occurance of “desirable” heritable characteristics.