Name:_______________________________

Internet Biology/Genes 2

The Human Transcript Map -- http://www.ncbi.nlm.nih.gov/science96/

 

Scroll down to the bottom of the page.  On the bottom, right-hand side is a "browse by chromosomes" section.  Access the chromosomes by clicking on the numbers in that section.  Answer the following questions on a separate piece of paper.  Use a dictionary if necessary.

 

1.        Chromosome 21/Lou Gehrig’s disease/after clicking on chromosome 21, click on SOD1.

 

What is Lou Gehrig’s disease?

 

It is a neurological disorder characterized by progressive degeneration of the motor neuron cells in the spinal cord and brain.  This disease results in paralysis and death.

  

Why is this called Lou Gehrig’s disease?

 

It is named after a New York Yankee baseball player who was forced to retired as a result of this disease.  This happened during the beginning of the last century.

 

2.        Chromosome 12/Phenylketonuria/after clicking on chromosome 12, click on PAH.

 

What is Phenylketonuria?

 

It is a rare metabolic disorder caused by a deficiency in a liver enzyme.  This disorder prevents the individual from metabolizing one of the essential amino acids found in all foods that contain protein.  If not treated early it can cause mental retardation, skin rashes, seizures, and irritable behavior. 

 

Why do we screen newborns for Phenylketonuria (PKU)?

 

If a baby is placed on a phenylalanine restricted diet then damaging effects of the disease can be controlled.

 

3.        Chromosome 7/Cystic Fibrosis/after clicking on chromosome 7, click on CFTR.

 

What is Cystic Fibrosis?

 

Cystic Fibrosis causes the body to produce thick, sticky mucus in the lungs.  It also affects the pancreas by blocking digestive enzymes.  These digestive enzymes are required by the intestines to digest food.

 

What would be the benefit of being tested for the CF carrier gene?

 

This is the most common fatal genetic disease in the United States today.  It would be important for a couple to be tested so that they can find out if one or both of them are carriers.

 

4.         Choose three different chromosomes and define a disease associated with those chromosomes.   Describe the advantage or disadvantage of carrying that gene.  Use the back of this page if needed.

 

Answers will vary.

 

 

 

 Click here F to return to Genetics Activity.