



What is genetics?

Picture of a model of a strand of DNA, magnified



Genetic illustration, chromosome
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Genes are lined up on the chromosomes in specific positions and locations. Although these locations are the same for each pair of chromosomes, the genes may be similar or different. Just as traits, such as blue eyes and curly hair, are passed from the genetic information of the parents to a baby, inherited diseases and abnormalities can also be passed on. Some disorders are recessive, meaning that the abnormal gene must be received from both parents. Other disorders are dominant, meaning an abnormal gene may come from only one parent for the disorder to occur.

When a gene is abnormal, or when entire chromosomes are missing or duplicated, defects in the structure or function of the body's organs or systems can occur. These mutations or abnormalities can result in disorders, such as cystic fibrosis, a recessive genetic disease, or Down syndrome, a condition that occurs when a baby receives three copies of the #21 chromosome.

Reviewed Date: 06-16-2013

