Human Heredity. Exceptions to the Rules Pedigrees Karyotypes Ethics. Examples of Dominant Disorders. Dwarfism Polydactyly and Syndactyly Hypertension Hereditary Edema
Exceptions to the Rules
rr = white
Rr = pinkIncomplete Dominance
NS = some of each
SS = sickle cells
NN = normal cellsCodominance
Colorblindness is an X-linked recessive trait.
Traits found on the X chromosome
Note that the trait can appear in offspring of parents without the trait.
Note that the trait appears in every generation and ½ the offspring of an affected heterozygote are expected to show the trait.
Changes in Chromosome Number and Structure
Down syndrome (trisomy 21)
The Frequency of Chromosome Non-Disjunction And Down Syndrome Rises Sharply with Maternal Age
The phenomenon is clear – the explanation isn’t.
Down Syndrome Male
Turner Syndrome Female
XYY Syndrome Male
Removing a cell for diagnosis from a human embryo. Syndrome Rises Sharply with Maternal Age
Pre-Implantation Genetic Diagnosis (PGD)
Amniocentesis and Chorionic Villus Sampling Syndrome Rises Sharply with Maternal Age
Many new techniques for learning about individual genes rather than whole chromosomes are available or under development.
12. In the film, a person could have a potential romantic partner sequenced. Discuss the positive and negative aspects of having this technology available to prospective mates.
16. You are an employer and know from genetic testing that the most qualified applicant for the job has a 70% chance of developing Multiple Sclerosis in one year's time. Would you hire this person? Why or why not?
14. During a scene in GATTACA, Vincent’s parents visited a doctor who specialized in child conception to select for the best traits for his future brother. They hoped that his brother would have the best possible chances for a successful life. Some of the traits mentioned in GATTACA included intelligence, height and any possibility of inheritable diseases. If you decided to have a child one day and are given the opportunity to select for special traits, would you do so? Explain why or why not.
15. Wouldn't every parent want to ensure that their child was perfect and had the attributes of physical attractiveness, intelligence and athletic prowess to be able to do whatever he or she wanted in life? If so, why is the society portrayed in this film so devoid of happiness, vitality and fun?
18. Cloning is a process in which you make a genetically identical organism. People say that this could be cool others say it is messing with Mother Nature. If you had the opportunity to clone yourself, would you do it and why?
19. If a couple had a baby who died and could not have any more babies, but had the opportunity to clone their baby, should they be allowed to clone it?
20. Stem cell research is another ethical issue. Stem cells are cells from an early embryo that can become any type of cell like a heart, lung, liver, or skin cell. The reason people are researching these cells are because you can actually grow new tissues and organs to replace damaged ones. For instance, it may be possible to grow a new set of lungs for someone dying of lung cancer. The ethical issue with this type of research is that in order to get this type of stem cells you have to destroy an embryo so it will never grow into a person. Do you think this research should be done? Why or why not?
17. What would you say to a friend who believed themselves to be solely a product of their DNA and with no true freedom?
13. The technology to do what was done in the movie is definitely possible within the next fifty years. Do you think that Vincent’s world could eventually happen in America? Why?