MODERN GENETICS

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MODERN GENETICS
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What is Cloning?

• Making an exact genetic copy of a cell, organ or
  an organism
• This process uses SOMATIC CELLS (non-sex cells)
  instead of sex cells because somatic cells
  contain a complete set of chromosomes (46).

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Basics of the Cloning ProcedureSomatic Cell
Nuclear Transfer

• This happens in vitro (outside the body in a
  petri dish).
• The nucleus of a somatic cell is placed inside an
  egg cell that has had its nucleus removed.
• Electricity sparks cell division of the egg cell
  and an embryo is formed.

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Basics of the Cloning Procedure

• An embryo is the form of the organism in its
  early stages. It is a group of undifferentiated
  cells.
• The embryo is placed in the uterus of the egg
  donor or surrogate mother.
• A surrogate mother is a female who carries the
  baby for another female.

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SCNT Class Example
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SCNT Cloning Activity

1. Color the somatic cell donor brown, the egg cell
   donor yellow, and the surrogate mother gray
   (light black). Cut all mice and morula out.
2. Cut out the somatic cell and place in Petri Dish
   1.
3. Cut out the egg cell and place in Petri Dish 2.
4. Cut out the egg cell nucleus and glue into Petri
   Dish 2. Add a note that it will be discarded.
   Glue the enucleated egg cell in Petri Dish 3.

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SCNT Cloning Activity

• 5. Cut out the somatic cell nucleus and glue it
  inside the egg cell in Petri Dish 3. Glue the
  enucleated somatic cell in Petri Dish 1.
• 6. Draw a lightning bolt next to Petri Dish 3
  to indicate that an electric shock is applied to
  the egg cell containing the somatic cell nucleus.
• Glue the morula (16 cell embryo) into the
  surrogate mother and glue down.
• Color the mouse pup the appropriate color and
  glue down. Clone of ________ cell donor.

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HISTORY OF CLONING

• 1953 frog
• 1996 sheep
• 1998 cow
• 2001 rabbit
• 2002 rat
• 2002 cat
• 2003 horse
• 2005 dog

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Cloning does not always produce expected results.
It is also expensive and inefficient!

• CC the cat cost 50,000 to create. Her genetics
  were the same as her clone, however she did not
  appear identical! Why?
• X-inactivation
• In females, 1 x sex chromosome is inactivated
  immediately after the egg is fertilized. CC had
  a different x inactivated!
• Horse- 841 attempts .12 efficiency
• Sheep- 277 attempts .36 efficiency

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Rainbow- Parent Clone
CC- Copy Cat
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Cloning Pros/Cons

• Pros

• Cons

• Can clone organs for transplant patients.
• Can help infertile couples have offspring
  genetically linked to one of the parents.
• Can increase populations of endangered species.
• Can bring back a deceased pet.
• Can replicate living things with desirable
  traits- like trees that grow quickly.

• Does not help to improve the genetic diversity of
  a species.
• Could create a black market for transplant
  organs-Create clones to harvest organs!
• Expensive and inefficient!

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STEM CELL RESEARCH

• What is a stem cell?
• A cell that is not yet differentiated into a
  specific type.
• Whats so special about embryonic stem cells?
• They are Pluripotent
• can become any of the 220 different cell types

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Why is the use of embryonic stem cells so
controversial?

• Removing a stem cell from an embryo for
  experimentation destroys the embryo.
• Is this murder?
• When does life begin?
• Read and discuss Embryos R Us Case Study

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Therapeutic potential

• Turn the stem cells into
• Pancreas cells to produce insulin to relieve
  diabetes
• Dopamine producing cells in the brain to relieve
  Parkinsons disease
• New limbs and failing organs

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Is it controversial to experiment on all stem
cells?

• In addition to embryonic stem cells, there are
  adult stem cells.
• Adult stem cells are found in many organs and
  tissues, including brain, bone marrow, blood and
  skin.
• These stem cells are multipotent which means they
  can only become a certain type of cell(s) .
• Their purpose is to maintain and repair the
  tissue in which they are found.

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Is it controversial to experiment on all stem
cells?

• Experimenting with adult stem cells is not
  controversial because it does not harm the adult
  if the cells are removed from the body.
• There has been some exciting recent research that
  has demonstrated the ability to turn adult stem
  cells into embryo-like stem cells. These are
  called induced pluripotent stem cells (IPSCs).

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Genetic Engineering

• gene- DNA sequence that codes for a protein.
• AATCGTAACCGGTTA
• genome -all the possible bases in a species or
  individual
• Human Genome Project (1990-2003) - All of the
  base pairs in the human genome have been
  sequenced (locations of genes on the 23
  chromosomes have been determined). The human
  genome has approximately 20, 500 genes.

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What is Genetic Engineering?

• The modification of the DNA in an organism or the
  exchange of DNA between organisms.
• Why would we want to do this?
• Genetic engineering can happen between different
  species because the DNA code is universal. All
  living things have ACGT nucleotides and the same
  amino acid coding scheme.
• AUG codes for methionine in all living things!

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Steps to Genetic Engineering

• 1. A gene of interest is removed from a genome.
• 2. The gene is attached to a vector
  (transporter) and delivered into a host cell
• 3. The host cell is put into a nutrient medium
  and allowed to divide many times to create many
  copies of the gene.
• 4. The host cell is inserted into the organism.

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How is a gene removed from a genome?

• Restriction enzymes- recognize a specific DNA
  sequence and cut the DNA wherever that sequence
  exists.

ATCGGATGAATTCTACCGATTAAG TAGCCATCTTAAGATGGCTAATTC
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How is the gene of interest separated from other
genes?

• Gel electrophoresis

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Gel Electrophoresis

• DNA samples are placed in a porous gel which is
  connected to an electric current.
• The current moves the DNA pieces and separates
  them based on their size. The smallest pieces
  move the fastest and end up at the bottom.
• We can use this technique to isolate genes,
  determine genetic relationships (paternity),
  determine evolutionary relationships, and solve
  crimes.

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What is a common vector used in genetic
engineering?

• Plasmids are circular DNA molecules found in
  bacteria that are often used for genetic
  engineering.
• The plasmid is cut with the same restriction
  enzyme used to cut out the gene of interest.
• Once the plasmid has the new gene, it is called
  recombinant DNA.

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Gene Therapy

• Humans can be genetically engineered.
• Normal genes can be inserted into cells
  containing defective genes in order to correct
  genetic disorders.

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Gene Therapy
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Paternity Testing

• If there is uncertainty about a childs
  biological father, DNA samples from the possible
  fathers can be compared with the DNA of the child
  and mother.
• All DNA samples are treated with the same
  restriction enzyme and are run on a gel by
  electrophoresis.
• A childs DNA pieces are a combination of pieces
  from the mother and father (each DNA band must
  match a band from one parent).

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DNA Fingerprinting to determine Paternity
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• Who is the father?
• Circle the smallest DNA fragment(s).
• Box the largest DNA fragment(s).

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Afather Bmother Are C and D both biological
children of A and B?
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Genetics Technology Bingo

• 1. Cloning
• 2. Induced pluripotent stem cells
• 3. Embryo
• 4. Multipotent
• 5. Surrogate
• 6. Mrs. McLoughlin
• 7. Gel electrophoresis
• 8. Plasmid
• 9. Adult stem cell
• 10. Genetic engineering
• 11. Electricity
• 12. Restriction enzyme

• 13. Gene therapy
• 14. Genome
• 15. Gene
• 16. Recombinant DNA
• 17. In vitro
• 18. Somatic cell
• 19. Somatic cell nuclear transfer
• 20. Vector
• 21. Uterus
• 22. X-inactivation
• 23. Embryonic stem cell
• 24. Pluripotent

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• Biotechnology Test Review Questions
• Easy
• Small, circular piece of bacterial DNA is called
  a ____.
• Give two examples of vectors
• The entire collection of genes within human cells
  is called the _______________.
• Difference between technology and biotechnology?
• Function of restriction enzymes?
• HGP stands for? How many base pairs in HG? How
  many proteins?
• Difference between surrogate and biological
  mother?
• A _____________ is caused by a defective or
  mutant gene.
• Define gene.
• The first cell created by sexual reproduction is
  called a

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• Medium
• 1. Inserting unrelated pieces of DNA together
  will result in ____________________.
• 2. IVF stands for? What is a synonym used for
  IVF?
• 3. What does transgenic mean?
• 4. Idenical twins are considered to be genetic
  ___________.
• 5. How does IVF work? What does the female have
  to do? What does the male have to do?
• 6. Why does IVF sometimes result in twins,
  triplets, or quads?
• 7. Difference between fraternal vs. identical
  twins?
• 8. How does Gel Electrophoresis separate DNA
  fragments?
• 9. What is an example of a genetic disease?
• 10. What kind of ethical questions arise from
  IVF?

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• Difficult
• What is the difference between gene therapy and
  genetic engineering?
• Difference between a hybrid and chimera?
• Steps of genetic engineering?
• The Hind R1 restriction enzyme is used to slice
  DNA at the GAATTC between the G and A.
  Illustrate how this enzyme would precisely cut
  the fragment
• ATTAGATCGCCCTAGAATTCAAGCTGGTAGCTAGCTACATCTA
• TAATCTAGAGGGATCTTAAGTTCGACCATCGATCGATGTAGAT
• What research can be done using gel
  electrophoresis?