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Cloning
IVF - in vitro
fertilisation
Stem
cells
Applications of
genetics
Human genome
project
Gene therapy
Genetic
engineering
Genetic
fingerprinting
ISSUES:
What happens to unused embryos? - Stem cell research?freeze
in liquid nitrogen for later? Destroy? Donate to others?
•hormones trigger ovulation - collected by ultrasound and tube
•male sperm ejaculated and stored in nutrient solution
• male sperm + oocyte into petri dish (100,000 :1) or
sperm injected into oocyte
• three days development of embryos
• two implanted in uterus
IVF
Cut meristem (tip/root areas) or
length from shoot
cut into small areas = explants
sterile, aerated nutient (agar)used
callus - mass of undifferentiated ce
growth hormones - shoots then roots
transplant into sterile soil
Totipotent - differentiated
adult cells give rise to
different cells
Embryo
cloning IVF,
embryo
splitting,
surrogates
Nuclear transplants - donor
cells taken (provide diploid
nucleus)
unfertilised egg (haploid)
from recipient cells fused egg cell programmed to
produce embryo
developing embryo
implanted = clone of donor
micropropagation
Plants
Animals
Production of genetically identical organisms
Cloning
Ethics - use of embryos, potential of human cloning
Medical research and
treatments e.g. virus
growth for vaccines (e.g.
flu), monoclonal
antibodies
Adult tissue
repair/replacement
e.g. skin damage,
blood cells,
respiratory/digestive
system linings
Cells can be grown in
labs with growth
factors controlled
(similar to cloning
Dolly)
Tissue engineering e.g.
growth of skin for burns
victims, cartilage, blood
vessels
Therapeutic use in medicine
e.g. use of a patients own
cells to grow organs e.g.
pancreas for diabetics, heart
- better than transplants (no
rejection); insertion into the
brain
(Parkinson’s/Alzheimer’s)
Source = bone marrow; embryonic cells.; umbilical cells
Undifferentiated cells which divide to give rise to cells that can become specialised
Stem
cells
Donor DNA
plasmid from bacterium/
vector
restriction endonucleases ;
sticky ends
DNA ligases; splicing
recombinant DNA
GM crops - transgenic plants
e.g. herbicide resistance in
soya plants; delayed ripening
in tomatoes
Inserted by bacteria
Products used in medical
treatment e.g. insulin, growth
hormones
Gene therapy (see later)
cloning
Antibiotic resistance marker
genes
Reverse transcription to produce
specific DNA for insertion:
mRNA -> cDNA-> DNA
fermentors - fitltration and
purification
reverse transcriptase DNA
polymerase
Genetic
modification
Issues: -benefits crops, medical treatments,
products not made by other methods. Release into
the environment of potential pathogens, resistance
into weeds/pathogens,interactions with other
genes, ethics e.g. the right to tamper with
genotypes in future
Identification of individuals carrying
the genes : pre-implantation, prenatal,
new-born, pre-symptomatic, carriers
(pre-conception)
Identification of mutated genes which
may cause genetic diseases e.g.
alzheimer’s, CF, diabetes, cancers establishing effects (diagnosis)
Manufacturing of
missing proteins/
designer drugs - genetic
engineering
Use of markers to identify
base sequences of normal
genes
Identification of the 25,000 genes (1990-2003)
Human genome
project
Issues Use of liposomes enter via the
phopholipid bilayer
Use of
viruses as
vectors
Genetic counselling
Genetic screening
Which genes should this be
used for?
Genetic engineering to extract
genes for producing missing
proteins
Abortions to avoid passing
on the gene?
Insertion of genetic material into
affected cells e.g. cystic fibrosis
sufferers respiratory cells
Somatic cell therapy
Insertion of corrective genes into
eggs - can be inherited
germ cell therapy
Gene
therapy
Issues:-storage, access,privacy
Restriction endonucleases
non-functional DNA = HVR/STR
different lengths (unique)
electrophoresis - -ve so move to +ve
(smallest move fastest)
nylon membrane- Southern blotting
radioactive/ chemi-luminescent probes
X-ray films
autoradiograph -> genetic fingerprint
PCR - manufacture of
multiple copies
DNA replication
DNA polymerase
short DNA pieces = primers
(signal to enzymes)
target DNA heated to 95°C
separate strands
cooled to 55°C - primers join
complementary bases
heat to 70°C - enzyme
polymerises second strand
repeat
DNA source e.g white
blood cells
Uses - forensic science (identification of criminal), paternity cases,
identification of species, evolutionary relationships
Genetic
fingerprinting