Transcript Chapter 1 A Perspective on Human Genetics

Chapter 14
Biotechnology and Society
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Biotechnology
• Uses recombinant DNA technology to
produce goods or services
• It is used in
– Agriculture
– Medicine
– Evolutionary studies
– Identification
– Criminal investigations
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Biopharming
• Production of medical molecules in other
organisms
• Examples
– Human insulin (1982)
– Growth hormone (1980s)
– Factor VIII (1990s)
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Transgenic Animals
• Genes are
transferred
between species
using recombinant
DNA technology
• Human AGLU from
rabbit milk for
treating Pompe
disease
Fig. 14.2
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
dsd.lbl.gov
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Use of reporter genes to monitor gene expression 1.
lac Z - beta galactosidase enzyme from bacteria
blue color when provided with appropriate
substrate
promoter of gene of interest
lac Z gene
Blue color anywhere that the gene is on
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Use of reporter genes to monitor gene expression 2.
gfp gene from jellyfish Aequoria victoria
fluoresces green when exposed to blue light
can monitor gene expression in living animals
many different variants now available - CFP/YFP/RFP etc
promoter of gene of interest
gfp gene
Green color anywhere that the gene is on
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
gfp variants
‘art’
bacteria expressing
different gfp variants
From lab of Roger
Tsien
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Using the GFP reporter gene..
Drosophila embryo
Mouse
C. elegans
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Biopharming
• Edible vaccines
– Still in development
• Genetically modified foods
– Transgenic crop plants with new
characteristics
• Transgenic crops
– Resistance to herbicides and disease
• Enhancement of nutritional value
• Concerns
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
A Foreign Gene is Transferred
Fig. 14.3
Fig. 14.3a
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Plant Cells Grows and Divides;
Embryos Develop
Fig. 14.3b
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Genetically Engineered Plants
Fig. 14.3
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Transgenic Cotton (left) Modified to
Resist Insects
Fig. 14.4
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Transgenic Crops in U.S. (1996-2003)
Fig. 14.5
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Genetically Modified Crops
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Enhancement of Nutritional Value
Golden Rice
• Vitamin A deficiency is a serious health
issue
• Modified the rice, a food staple
• Two genes from daffodils and one from
bacteria were inserted into rice
• With added genes rice plants synthesize
beta-carotene
• When the rice is eaten it is converted to
Vitamin A
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Golden Rice
Fig. 14.6
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
The Flavr Savr tomato
home.cc.umanitoba.ca
transgenic for gene that slows ripening process
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Concerns
• Transgenic crops have created
controversy
• Safety issues
• Environmental issues
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Transgenic Models of Human Disease
• 90% of human genes are also present in the
mouse
• Excellent model of human disease
• Transgenic models have several goals
– Produce an animal with symptoms that
mirror those in humans
– Use the model to study the development
and progress of the disease
– Test treatments that hopefully will cure the
model organisms of human disease
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Producing the Transgenic Model
• A copy of Human HD gene was cloned into
a vector
• Vector carrying the HD gene was
microinjected into the nucleus of a
fertilized egg
• Injected eggs transplanted into a foster
mother
• After pups were born tail tip DNA was
analyzed for the presence and expression
of HD gene
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Mouse model for huntington’s disease
WT
Transgenic mouse
www.hopkinsmedicine.org
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Animal Models
for Human
Diseases
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Prenatal Testing Can Diagnose Sickle
Cell Anemia
• Mutation destroys cutting site for the
enzyme MstII, producing fewer fragments
• Prenatal testing uses amniocentesis or
CVS
• Embryo testing and polar body biopsy can
be done
• Risks of testing
• Presymptomatic testing
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Sickle Cell
Anemia
Fig. 14.8
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
DNA Microarrays Screen for All
Known Mutations
Fig. 14.11
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
DNA Microarray after Hybridization
Fig. 14.12
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Human p53 gene
Fig. 14.13
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
DNA for Identification
• Technology developed in the 1980s
• Alec Jefferys and colleagues discovered
variation in 14–100 base pair DNA
sequences located at many different
chromosomal sites called microsatellites
• A DNA fingerprint or profile of an
individuals is produced by evaluating the
variation in the microsatellites or shorter
short tandem repeats (STR)
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
DNA Profiles
• Short tandem repeats (STRs)
Short sequences ranging from 2–9 base
pairs in length, for example:
CC TTCCC TTCCC TTCCC TTCCC TTCCC TTC
• DNA profiles are based on variation in the
copy number of DNA sequences
• DNA profile is unique to an individual or
their monozygotic twin
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Variation in STR in Two Individuals
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Uses of DNA profiles
• Criminal investigations
• Identification of remains
• Identification of species
• Identifying family members
• Biohistorical information
• Paternity testing in humans and
animals
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Probabilities in DNA Profiles
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Different Alleles of a STR
Fig. 14.14
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Analyzing DNA
Profiles
Fig. 14.15
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
www.scq.ubc.ca
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
DNA fingerprinting using VNTRs
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Stem cells
Prenatal genetic testing
Saunders
Brower
April 26 Gorenkoff
Magee
Shriner-Cahn
Kwak
Chatterjee
Cho
Lawrence
Damiano
Olson
Cheis
Cloning of animals/humans
Bondurant
Lapides
Simon
Vigneron
Prada
Siegel
May 2
Genetically modified
plants/animals
Too much technology?
Powers
Rosenblum
Le
April 30
Sotomil
Coyle
Kropp
Spiwak
Davidson
Fei
Grossman
Marwell
Roth
Behavioral genes
Seplowitz
Rich
Lenard
Collins
Dionne
Rudberg
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
Problem Set 5
Due on April 11
Term paper is due on Wednesday, May 9 by 5 pm
(via email or paper)
Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning
EXAM 2
High - 86
Low - 25
Average - 60.5
A
14
B
C
12
10
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Please see me
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Chapter 14 Human Heredity by Michael Cummings ©2006 Brooks/Cole-Thomson Learning