Applications of genetics

1
Cloning
IVF - in vitro fertilisation
Stem cells
Applications of genetics
Human genome project
Genetic fingerprinting
Genetic engineering
Gene therapy
2
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
3
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

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
Embryo cloning - IVF, embryo splitting, surrogates
Totipotent - differentiated adult cells give rise
to different cells
micropropagation
Plants
Animals
Production of genetically identical organisms
Cloning
4
Ethics - use of embryos, potential of human
cloning
Medical research and treatments e.g. virus growth
for vaccines (e.g. flu), monoclonal antibodies
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
(Parkinsons/Alzheimers)
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)
Source bone marrow embryonic cells. umbilical
cells
Undifferentiated cells which divide to give rise
to cells that can become specialised
Stem cells
5
GM crops - transgenic plants e.g. herbicide
resistance in soya plants delayed ripening in
tomatoes Inserted by bacteria
Donor DNA plasmid from bacterium/
vector restriction endonucleases sticky
ends DNA ligases splicing recombinant DNA
cloning Antibiotic resistance marker
genes fermentors - fitltration and purification
Products used in medical treatment e.g. insulin,
growth hormones
Gene therapy (see later)
Reverse transcription to produce specific DNA for
insertion mRNA -gt cDNA-gt DNA reverse
transcriptase DNA polymerase
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
Genetic modification
6
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. alzheimers, 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
7
Issues - Genetic counselling Genetic
screening Which genes should this be used for?
Abortions to avoid passing on the gene?
Use of liposomes - enter via the phopholipid
bilayer
Use of viruses as vectors
Genetic engineering to extract genes for
producing missing proteins
Insertion of genetic material into affected cells
e.g. cystic fibrosis sufferers respiratory cells
Insertion of corrective genes into eggs - can be
inherited
Somatic cell therapy
germ cell therapy
Gene therapy
8
PCR - manufacture of multiple copies
DNA replication DNA polymerase
short DNA pieces primers (signal to
enzymes) target DNA heated to 95C separate
strands cooled to 55C - primers join
complementary bases heat to 70C -
enzyme polymerises second strand repeat
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 autoradiogra
ph -gt genetic fingerprint
DNA source e.g white blood cells
Uses - forensic science (identification of
criminal), paternity cases, identification of
species, evolutionary relationships
Genetic fingerprinting