As scientists learn more about genetics, they are able to look at how some medical conditions are caused by abnormalities in DNA as well as how some diseases can be inherited. You will learn about genetics and health in this activity.

Some genetic disorders can be the result of a mutation in a single gene. Other disorders are the result of missing or extra chromosomes. Mutations occur naturally when a mistake is made at the time that cells copy their DNA before cell division. Mutations can also result from environmental factors such as exposure to harmful chemicals, ultraviolet light (sunshine), or nuclear radiation that can damage DNA.

  Cancers of the colon, breast, and ovaries, as well as Alzheimer's disease have been found to be caused by a mutation of one gene. Diseases such as Huntington's, Turner syndrome, and sickle cell have been linked to chromosomes that are either missing, changed, or duplicated. Cystic fibrosis and Down syndrome have been found to result from mutations in several genes.     

The advantage to learning that these diseases have a genetic link is that research can be done to see if ways to repair the chromosomes or prevent the diseases in future generations are possible.

As scientists get a better understanding of heredity, DNA, chromosomes, and genes, they may make many discoveries that could have positive influences on your health. Some of the changes that have or may come about as a result of genetic research include the following:

• Improved diagnosis of disease occurs by recognizing changes or abnormalities in DNA as well as by learning more about links among various diseases and specific genes or chromosomes.

• Genetic predisposition to disease is detected by studying family histories and knowing how disease is passed from one generation to the next.

• Gene therapy research explores the possibility of repairing or replacing genes that have defects.

• Prevention of disease might involve having people with a genetic predisposition to some diseases avoid the environmental conditions that trigger the disease.  
  

• Organ donation may be made easier and more effective by matching donors and recipients more closely.

• Genetic research in agriculture may lead to production of more nutritious foods as well as foods that are less likely to suffer from disease.