Nexa is a role playing exercise set in the next century after a nuclear war that destroys most of the present civilization. Groups of students act as genetic technicians making difficult choices concerning survival in this grim sci-fi future.
Biology topics involved: genetics, genetic disorders and bioethics.
Warning: this role playing exercise may upset some students.
Notes to the Teacher:
This exercise will take 2 - 3 class periods.
Divide the class into groups of 3 - 4. If you want to set the right tone for this exercise, show a short clip of a video depicting the aftermath of a nuclear war. Use your imagination for this part.
You can read the scenario to the students or have them read it themselves. They may need a copy to refer to.
Warning: this role playing exercise may upset some students.
An unit on introductory genetics would be useful but not necessary.
Read the following scenario.
Nobody knows for sure who exactly caused the
Great War. It could have been terrorists from a third world country.
It could have been an upset general, a disgruntled employee or a computer
glitch. It doesn't matter because the result was the same.
The Great War was a world wide, devastating, nuclear war. Most of
human civilization ended at the beginning of the third millennia.
This is the year 2051. The large population centers from the previous
century were completely wiped out leaving radioactive areas devoid of life.
The nuclear winter that followed the nuclear war changed the climate considerably
and destroyed crop production for almost a decade following the war.
Biopathogens were released in many parts of the world rendering these areas
uninhabitable. All the vertebrates in Australia including humans
died off due to biopathogens. Insects are the highest life forms left in
some parts of the world. Humans are durable by nature and have survived
in certain isolated, sheltered enclaves. These enclaves are very overcrowded.
They are filled with many people squeezed into small geographic areas and
have little food available. Conditions are harsh. The
health care system consists of only a few hospitals in each enclave to
take care of numerous people. You live in Nexa, which is a small,
overcrowded area of barely habitable land along the eastern coast of what
was once a state called Texas. It used to be part of a large country
called the United States. Nexa raises most of its food in greenhouses.
Fish from the ocean are not eaten unless they are tested carefully.
Large domesticated insects such as the mutated, 12 inch long cockroaches
provide a major protein source for the people of Nexa. Nexa consists
of three population centers (New Hope, Good Hope and Last Hope) squeezed
into adjoining parts of Nexa. You are approximately 27 years old
and were born after the Great War. You were lucky enough to have
been chosen to continue in school and become a professional. Professionals
live in a clean apartments in a nice part of New Hope, and have a good
food allowance. Their families are treated well.
You are a geneticist. You work as part of a genetic technology team in a large hospital. Your job is very important and challenging. The radiation of the nuclear fallout from the Great War and mutagenic chemicals released into the environment during the last century have increased the number of genetic diseases. Unfortunately, medical science has not improved much in the last 50 years due to the terrible conditions after the Great War. The team members are to do genetic testing on expectant mothers that come to the hospital and evaluate which offspring will be allowed to develop to full term. Remember conditions are harsh, people are starving everyday and the health care system is over loaded. Your society is barely surviving. Your family well-being depends on your status as a professional. Nexa is not a pleasant place to live!
Description of the Most Common Genetic Disorders in Nexa:
Cougher - Children with this disorder begin coughing shortly after birth. Heavy mucus production in the throat and lungs causes breathing problems that worsen with age. Most individuals usually die in their late teens due to related respiratory diseases or complete blockage of the breathing passages. The severity of the disease can vary between individuals. Females with Cougher's usually live longer on the average. Exercising and diets low in fats can add up to 10 years to a Cougher's average life span. This autosomal recessive disorder does not affect intelligence.
Patches - Children with this disorder are born with large patches of rough reddish skin. As the children mature, the patches increase in size, become rougher and change from the original red color to a purple color and finally a black color. When the individual becomes completely covered with rough black patches, their immune system becomes inactive and they quickly die of a wide variety of infections. The average life span of an individual with Patches is approximately 30 years. This autosomal recessive disorder does not affect intelligence.
Dumbing - Children with Dumbing disease seem to be normal at birth and for the first year afterwards. Each successive year, the intelligence level drops very slowly but steadily. By their twenties, individuals with Dumbing disease are usually profoundly retarded and need constant care. If constant care is provided, in some cases the individual might live another 20 years. Varying the diet does not seem to help slow down the progress of this autosomal recessive disease.
Stripes - Children with Stripes are born lacking skin pigments. Their bodies are mainly pale white except for some black stripes that occur in the hair and skin. Stripes also have pale, light-blue eyes. They sunburn easily and are prone to skin diseases and allergies. They have a normal life span if they avoid being outside in bright sunlight. This autosomal recessive disorder does not affect intelligence.
Fainter - Children with Fainter's disease tend to pass out easily when upset. They get progressively worse as they get older. When faced with any threatening or emotional situation, they will collapse immediately. In a crowded society such as Nexa, these people are faced with many difficulties. Because Fainters tend to bleed easily, injuries from falling can be life threatening. Most individuals with Fainter's die by their late teens or early twenties due to trauma to the head from constant falls. There is a anti-fainting factor that can be isolated and produced from normal blood but is too expensive for most people with Fainter's. This X linked disorder does not affect intelligence.
Drooler - Individuals with Drooler's disease produce large quantities of saliva, sweat and urine from early childhood. Individuals require the intake of large quantities of liquids and special diets to prevent becoming dehydrated or malnourished. With minor medical care and common sense these individuals live normal life spans and are usually very intelligent. This is a X linked disorder.
Shaker - This disease does not usually show up until the individuals are adults in their late twenties. The first signs of Shaker's disease are minor muscle tremors. Violent shaking of the limbs and spasms are common in Shakers that are in their 30's and 40's. Most Shakers die before their 50's due to heart related problems. This autosomal dominant disorder does not affect intelligence.
Cat - Individuals with Cat's disease are born with large pointed ears, cat-like eyes and pointed faces. When the teeth grow in, they are usually sharp and pointed. Excessive body hair develops as the child grows older. Adults are usually very large and strong. They have limited manual dexterity due to claw like deformities of the hands. Cats have a normal life span but their intelligence is slightly below average. This autosomal recessive disorder is associated with sterility.
Wasting - Children with Wasting disease seem to be normal at birth, but soon start wasting away. Changing diets, increasing food intake and medications have no effect. The children do not thrive and continue to gradually lose weight. They die within 2 to 3 years. The intelligence level seems to be adversely affected as the disease progresses. Wasting disease is caused by an autosomal recessive disorder.
Mosaics - Children with Mosaic appear to be normal males at birth. At about puberty, they start to grow rapidly, develop breasts, rounded hips and higher voices. Mosaic individuals are usually exceptionally tall, have above average intelligence and are always sterile. This is a X linked disorder.
Stills - Children with Stills are normal at birth. As the child gets older, they slowly lose control of the skeletal muscles. They lose the ability to walk, then the ability to use their hands and arms, and finally the ability to talk. Most Stills die in their twenties but a few survive into their forties with extensive medical care. Stills have a normal intelligence level and are always females. Females with Stills carry the trait on both X chromosomes. Females that carry the Stills trait on just one X chromosome seem to be normal. Our geneticists suspect male embryos carrying the Stills trait do not develop.
Alligator - Children with Alligator's
disease look normal when born, but soon develop dry, scaly skin.
By the time, the child is 4 or 5, the dry scaly skin has developed into
soft plates of skin. These plates harden and get larger, as the child
becomes a teen. Adult Alligators' bodies are covered with a thick,
plate-like, hard outer covering. Some of the plate-like scales found
on adult Alligators are bright colored and very shiny. Other characteristics
include ears that are usually reduced in size or missing completely, an
absence of body hair, the ability to survive with little water consumption
and a high fertility rate. Alligators tend to have a longer than
average life span. This autosomal dominant disorder does not affect
Genetic Technician (Student) Directions
Genetic Technician (Student) Directions:
Go through the list you have created on the
right side of the page above and label each genetic disorder with either
a S or a T. The ones labeled with a S will be saved and the ones
labeled with a T will be terminated. (A third choice may be available
- Some embryos could be checked to see if genetic markers for extreme intelligence
are present and labeled Q. This is quite expensive and can not be
used over once or twice.) This is to be a group decision and must
be defended if Nexa authorities question your decisions.
Genetic Supervisor (Teacher) Directions:
The Encyclopedia of Genetic Disorders and Birth Defects by James Wynbrandt and Mark D. Ludman from Facts on File, Inc., 460 Park Avenue South, New York, N.Y., 10016, 1991