Biotechnology

polarbearfellowshipBiotechnology

Dec 12, 2012 (4 years and 6 months ago)

282 views

Lecture #9



Date _____

Chapter 20~


DNA Technology

& Genomics

Biotechnology

Biotechnology:

manipulation of
organisms or their components to
perform practical tasks or provide
useful products

Practical DNA Technology Uses

Diagnosis of disease

Human gene therapy

Pharmaceutical products
(vaccines)
http://highered.mcgraw
-
hill.com/sites/0072437316/student_view0/chapter16/anima
tions.html#


Forensics

Animal husbandry
(transgenic organisms)

Genetic engineering in
plants

Ethical concerns?

Selective breeding

Mating organisms to
produce offspring with
desired traits (has been
around since ancient
times)

Inbreeding= mating
between closely related
individuals

Hybrids


offspring of
parents with different
forms of traits. In plants,
hybrids are often stronger
or bigger.

Recombinant DNA

Recombinant DNA:

DNA in
which genes from 2 different
sources are linked

Genetic engineering:

direct
manipulation of genes for
practical purposes. (cutting out
DNA from one organism and
putting it into another.) (i.e. how
we make recombinant DNA)

Transgenic organism= an
organism with recombinant DNA


C:
\
Documents and
Settings
\
BBAUGHMAN
\
Desktop
\
COURSES
\
AP
BIO
\
articles


C:
\
Documents and
Settings
\
BBAUGHMAN
\
Desktop
\
COURSES
\
LSS
I Summer Institute Resources
\
LSSI Prog.
Resources
\
GFP Mice

Genetic Engineering Tools

Restriction Enzymes

DNA ligase

Vectors


Plasmids!


Viruses

Reverse Transcriptase


Making recombinant DNA

Restriction enzymes
: in nature,
these enzymes protect bacteria
from intruding DNA; they cut up
the DNA (restriction) and are
very specific


Restriction site
:




where the restriction enzyme
cuts the DNA (a specific sequence)


Sticky end
: short single
-
stranded
extensions of restriction fragments
(segments of DNA cut by
restriction enzymes in a
reproducible way)

Restriction Enzymes

QuickTime™ and a
Cinepak decompressor
are needed to see this picture.
C:
\
Documents and Settings
\
BBAUGHMAN
\
Desktop
\
bio
powerpoints
\
Chapter 13 BDOL IC

http://highered.mcgraw
-
hill.com/sites/0072437316/student_view0/chapter16/animations.html#


DNA ligase
:

enzyme that can
join the sticky ends
of DNA fragments
(called gene
splicing)

Vector: Something
that carries foreign
DNA into a cell.


Bacterial
plasmids… small
circles of DNA


viruses


Reverse Transcriptase


Catalyses the production of DNA from
RNA


Why is this helpful in making recombinant
DNA?


Hint: Think about introns and exons…


Ex. Bacteria that make human insulin…

RNA viruses

Where does Reverse
Transcriptase come
from?

Answer:

Retroviruses: transcribe
DNA from an RNA
template (RNA
---
>DNA)


DNA gets incorporated as
provirus in host

Ex. HIV

http://highered.mcgraw
-
hill.com/sites/0072437316/student_view0/chapter
26/animations.html




http://www.pbs.org/wgbh/nova/aids/action.h
tml


Bacterial plasmids in gene cloning

Gene Cloning

Clone = genetically
identical copy

Gene cloning: Making
more copies of a gene


Bacterial plasmid
with recombinant
DNA reproduces as
the bacteria
reproduce.


C:
\
Documents and
Settings
\
BBAUGHMAN
\
Desktop
\
bio
powerpoints
\
Chapter 13 BDOL IC


QuickTime™ and a
Cinepak decompressor
are needed to see this picture.
Steps for eukaryotic gene cloning

Isolation of cloning vector
(bacterial plasmid) & DNA
(gene of interest)

Insertion of gene of interest
into the cloning vector (how?)

Introduction of cloning vector
into cells (transformation by
bacterial cells)

Cloning of cells (and foreign
genes)

Identification of cell clones
carrying the gene of interest


(nucleic acid hybridization


use radioactively labeled
nucleic acid probe)
or


look for protein product
http://highered.mcgraw
-
hill.com/sites/0072437316/student_view0/c
hapter16/animations.html#


Examples of GMO’s

Beta
-
carotene rice (a.k.a. Golden rice,
vitamin A rice)
--

daffodil and soil
bacterium genes

Bt corn and other crops


Bacillus
thuringiensis gene.

Terminator technologies


cause sterility of
seeds.


Gene Therapy

Germ line Therapy:
reproductive cells


affects
offspring

Somatic Therapy: body cells
of an individual


Ex. White blood cells
of SCID (severe combined
immunodeficiency)


Blood cells are
removed


Use of viral vector


Blood cells replaced,
having needed gene.


Risks?

Animal Cloning


Clone= a group of genetically
identical organisms or a group
of cells derived from a single
parent cell.



ex. Dolly the sheep


Somatic cell nuclear transfer


Remove Nucleus from an
egg


Fuse this unfertilized egg
with a body cell


Ethical issues


Reproductive cloning


Therapeutic cloning


creation of an embryo to
provide stem cells


http://videos.howstuffworks.com/hsw/11818
-
genetics
-
cloning
-
video.htm


DNA Analysis & Genomics

PCR (polymerase chain
reaction)

Gel electrophoresis

Restriction fragment
analysis (RFLPs)

DNA sequencing

Human genome

project


Polymerase chain reaction (PCR)

Amplification of any piece
of DNA without cells (in
vitro)

Materials: heat, primers
(single
-
stranded DNA),
DNA polymerase,
nucleotides,

Applications: fossils,
forensics, prenatal
diagnosis, etc.

http://highered.mcgraw
-
hill.com/sites/0072437316/student_view0/chapter16
/animations.html#


DNA Analysis

Gel electrophoresis
: separates nucleic acids or
proteins on the basis of size or electrical charge
creating bands of DNA consisting of pieces of the
same length.

Used in DNA Profiling


Paternity tests


Forensics

Ethical issues?

Good DNA ANALYSIS COMPUTER LAB ACTIVITY=
http://www.biology.arizona.edu/human_bio/activities/blackett/introduction.html


See Activities for in class simulation to be used for forensics and paternity tests




How does gel electrophoresis work?


DNA is cut with restriction enzymes and added to a well.

The negative DNA is attracted to the positive electrode.

smaller pieces of DNA move faster through the pores in the
gel


A unique banding pattern is observed.


The
human genome

is estimated to be about 3 billion base pairs long and to contain 20,000
-
25,000 distinct genes



Gel Electrophoresis

animation
http://www.sumanasinc.com/webcontent/anisamples/majorsbiology/g
elelectrophoresis.html

http://www.dnalc.org/ddnalc/resources/animations.html



http://learn.genetics.utah.edu/units/biotech/gel/

good gel electrophoresis
virtual lab

DNA Analysis (continued)

Restriction fragment length polymorphisms (RFLPs)= differences
between different individuals in lengths of restriction fragments


Found especially in satellite DNA (highly repetitive non
-
coding
sequences of DNA)

RFLP animation
http://highered.mcgraw
-
hill.com/sites/0072437316/student_view0/chapter16/animations.html#



Southern blotting
: process that reveals sequences and the RFLPs in
a DNA sequence
http://highered.mcgraw
-
hill.com/sites/0072437316/student_view0/chapter16/animations.html#


O.J. Simpson capital murder case,1/95
-
9/95


Odds of blood in Ford Bronco
not

being R. Goldman’s:


6.5 billion to 1

Odds of blood on socks in bedroom

not
being N. Brown
-
Simpson’s:

8.5 billion to 1

Odds of blood on glove

not

being from R. Goldman, N.
Brown
-
Simpson, and O.J. Simpson:

21.5 billion to 1

Number of people on planet earth:

6.1 billion

Odds of being struck by lightning in the U.S.:

2.8 million to 1

Odds of winning the Illinois Big Game lottery:

76 million to 1

Odds of getting killed driving to the gas station to buy a
lottery ticket

4.5 million to 1

Odds of seeing 3 albino deer at the same time:

85 million to 1

Odds of having quintuplets:

85 million to 1

Odds of being struck by a meteorite:

10 trillion to 1


DNA Sequencing

Determination of nucleotide
sequences

Genomics: the study of
genomes based on DNA
sequences

Genome: all of an
organism’s genetic material.

Human Genome Project
Animations:
http://www.genome.gov/250
19885


Human Genome Project

Outcomes:


Identification and sequencing of genes
involved in traits and disease.


Genetic testing improved.


Greater understanding of genetics.


Ethical issues with genetic testing etc.
\


http://www.pbs.org/wgbh/nova/sciencenow/arch
ive/title
-
m
-
z.html

Public Genomes or
Personal genetic Testing