+ Should we or shouldn’t we? Biotechnology & Bioethics

+ Biotechnology The application of scientific and engineering principles to biological agents to provide goods and services to better human life Many moral issues today are centered around genetic engineering via the manipulation of DNA

+ Ethics Moral philosophy Discipline concerned with what is morally good and bad, right and wrong

+ Bioethics Discipline dealing with the ethical implications of biological research and the applications of that research Deals with the questions relating to the appropriate use of new technologies

+ There are no simple answers to ethical dilemmas…. What will cause the greatest good for mankind?

+ The Basics & More A review

+ 23 Pairs = 46 TOTAL Chromosomes

+ Autosome vs. Sex Chromosome Autosomes -first 22 homologous pairs Sex Chromosomes last pair (23 rd) that determine the sex of an individual

+ Autosomal Traits 2 Types of Traits: Autosomal Dominant AA, Aacarrier Autosomal Recessive aa

+ Sex-Linked Traits – on X Typically Recessive Expresses Trait: Male - X a Y Female - X a X a No Expression: Male - X A Y Female - X A X A or X A X a carrier

+ Biotechnology DNA Fingerprint Karyotyping Pedigrees GMO Cloning

+ Karyotyping

+ What are Chromosomal Mutations? Damage to chromosomes due to physical or chemical disturbances or errors during meiosis. Two Types of Chromosome Mutations: 1. Chromosome Structure 2. Chromosome Number

+ Problems with Chromosome Structure: 1. Deletion – during cell division, especially meiosis, a piece of the chromosome breaks off, may be an end piece or a middle piece (when two breaks in a chromosome occur). 2. Inversion – a segment of the chromosome is turned 180°, same gene but opposite position 3. Translocation – movement of a chromosome segment from one chromosome to a non-homologous chromosome 4. Duplication – a doubling of a chromosome segment because of attaching a broken piece form a homologous chromosome, or by unequal crossing over.

+ Problems with Chromosome Number Trisomy – having three of a particular type of chromosome (2n + 1) Monosomy – only one of a particular type of chromosome (2n -1) Polyploidy – having more than two sets of chromosomes; triploids (3n = 3 of each type of chromosome), tetraploids (4n = 4 of each type of chromosome).

+ How do you think Chromosomal Mutations with differing number of chromosomes develops? Monosomy and Trisomy due to Nondisjunction – members of homologous chromosomes do not move apart in Meiosis I or sister chromatids do not separate during Meiosis II leaves one cell with too few chromosomes and one cell with too many. Triploids develop from the fertilization of an abnormal diploid egg, produced from the nondisjunction of all chromosomes. Tetraploids develop from the failure of a 2n zygote to divide after replicating its chromosomes, subsequent mitosis would produce 4n embryo. Polyploidy is common in the plant kingdom, spontaneous origin of polyploid individuals plays important role in evolution of plants. In the animal kingdom, natural occurrence of polyploids is extremely rare. In general, polyploids are more nearly normal in appearance than having monosomy or trisomy, which is more disruptive to have one extra chromosome in a pair.

+ Pedigrees

+ Pedigree –genetic family tree Symbols and Rules: Male = Female = Affected = Unaffected = Carrier = Link parents together with a line and then make a vertical line to connect to offspring.

+ Autosomal Dominant Pedigree Draw a Pedigree showing a cross between Heterozygous parents that have 2 boys and 2 girls. Genotypes of Affected and Unaffected: AA and Aa = Affected aa = Unaffected Aa AA aa

+ Autosomal Recessive Pedigree Draw a Pedigree showing a cross between Heterozygous parents that have 2 boys and 2 girls. Genotypes of Affected and Unaffected: AA=Unaffected Aa=Carrier, Unaffected aa=Affected Aa AAaa

+ Sex-Linked Recessive Pedigree Draw a Pedigree showing a cross between a Red eyed Male fruit fly and a Carrier Female fruit fly which have 2 males and 2 females. Red is dominant to white. Genotypes of Parents: Male = X R Y Female = X R X r XRYXRYXRXrXRXr XRYXRY XrYXrY XRXRXRXR XRXrXRXr

+ Autosomal Dominant Traits Heterozygotes are affected Affected children usually have affected parents. Two affected parents can produce an unaffected child. (Aa x Aa) Two unaffected parents will not produce affected children. (aa x aa) Both males and females are affected with equal frequency. Pedigrees show no Carriers.

+ Autosomal Recessive Traits Heterozygotes are Carriers with a normal phenotype. Most affected children have normal parents. (Aa x Aa) Two affected parents will always produce an affected child. (aa x aa) Two unaffected parents will not produce affected children unless both are Carriers. (AA x AA, AA x Aa) Affected individuals with homozygous unaffected mates will have unaffected children. (aa x AA) Close relatives who reproduce are more likely to have affected children. Both males and females are affected with equal frequency. Pedigrees show both male and female carriers.

+ Sex-Linked Recessive Traits More males than females are affected. An affected son can have parents who have the normal phenotype. (X A Y x X A X a ) For a daughter to have the trait, her father must also have it. Her mother must have it or be a carrier. (X a Y, X a X a, X A X a ) The trait often skips a generation from the grandfather to the grandson. If a woman has the trait (X a X a ), all of her sons will be affected. Pedigrees show only female carriers but no male carriers.

+ Autosomal Dominant Disorders DwarfismPolydactyly and Syndactyly Progeria

+ Autosomal Recessive Disorders Congenital Deafness Sickle Cell anemia Albinism

+ Sex-Linked Recessive Disorders Red/Green Colorblindness Hemophilia Deafness Cataracts

+ DNA Fingerprinting

+ DNA Fingerprint  DNA fragments show unique patterns from one person to the next.  Used in paternity disputes and as forensic evidence.

+ RFLP- pieces of DNA cut up by enzymes Restriction Fragment Length Polymorphism (RFLP) Nucleotide sequence variations in a region of DNA that generates fragment length differences according to the presence or absence of restriction enzyme recognition sites.

+ Gel Electophoresis RFLP animation

+ Diagnose Disease

+ Paternity Testing

+ Forensics DNA Fingerprinting Animation

+ Genealogy

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+ Making an EXACT copy of an individual Cloning

+ Reproductive Cloning Creating a genetically identical organism Many animals have been successfully cloned

+ CloningHow it is done

+ Industrial Cloning

+ Therapeutic Cloning Cloning Individual Human Cells Involves Stem cells – precursor cells that give rise to specialized cells/multiple tissue types Allows for the generation of human tissue and organs Enhances our understanding of human development and serious medical conditions (cancer, birth defects, etc) Embryonic vs Adult Stem Cells

+ Have we made a Human Clone? NOT YET

+ VIDEO

+ Eugenics An effort to breed better human beings Encourage “good genes” Discourage “bad genes” Fear of history – Sterilization of the mentally ill in early America Nazi concentration camps

+ Genetic Testing Individual risk assessment based upon a person’s DNA profile DNA chip identifies genetic predispositions Potential for genetic discrimination DNA profiling? DNA banks?

+ PreImplantation Genetic Diagnosis (PGD) Diagnosing inherited genetic disorders “in vitro” Choosing which embryos will be transferred to the uterus based upon desired traits Gender decisions “Designer Babies?”

+ Are Designer Babies Real?

+ Genetically Modified Organisms GMO

+ How GMOs are made:

+ Transgenic Plants Engineered plants that contain novel genes from other species Results in new characteristics that make plants more desirable and useful to humans GMO Foods Video Are they safe to eat? How do they affect the ecosystem?

+ Transgenic Animals Engineered animals that contain novel genes from other species Results in animals that are more desirable and useful to humans Goats VIDEO Are they safe to eat? Where do we draw the line?

+ Xenotransplantation Harvesting organs from animals for organ transplantation into humans Severe Organ donor shortage Pigs – Perfect match! Do we have the right? PETA Dangers of Creating New Human Viruses Video

+ Finding a Balance Focusing on whether or not “we could” Instead of whether or not “we should” Weighing the Pros versus the Cons Acknowledging the tremendous responsibilities that must be faced with the information that we have acquired.