Colon Cancer, The Genetic Factor
Medical Author: Dennis Lee, MD
Medical Editor: Jay W. Marks, MD, and
K. Hecht, Ph.D.
cancer is the fourth most common cancer in the
United States. In the US an estimated 130,000 men and women will develop colon
cancer and more than 50,000 will die from it each year. The life-time risk for
individuals to develop colon cancer is approximately 6%, but the risk increases
to 18% among individuals who have a first degree relative (parent, sibling or child) with
What causes colon cancer?
Mutant genes cause colon cancer. The human body is composed of trillions of
cells. Inside each cell are two sets of 23 chromosomes, one set
from each parent. Each chromosome contains long strands of DNA. The DNA encodes thousands
of genes. The genes carry the genetic information that is passed down from both
parents. Different genes are responsible for different structures and functions
in the body. For example, some genes influence eye color, hair color, height,
and other physical characteristics. Other genes regulate cell growth and
division. Still other genes prevent cells from invading neighboring tissues or
spreading to distant organs.