Who is at risk for FAP?
Each child of a parent with FAP has a 50%
risk of inheriting the disease gene. If an affected parent has four
children, this does not mean that two children will have FAP. The
chances are the same in each pregnancy that the FAP gene will be
passed on by the parent with FAP. FAP affects males and females
of every race and ethnic group. FAP does not skip generations.
In the past, neither doctors nor scientists
could predict who would be diagnosed with FAP until adenomas developed
in the large intestine. However, in 1991, the gene
responsible for FAP was discovered and was named the Adenomatous
Polyposis Coli, or APC, gene.
Genes are the units of heredity which decide
our sex, eye/hair colour, build, and, sometimes, susceptibility
for certain diseases. We now know that about 100,000 genes do their
work inside each human cell. Genes contain all the information the
cell needs to carry on its production of protein and energy, like
an encyclopedia. Deoxyribonucleic acid, or DNA,
is the language of the genes, the master chemical. When cells divide,
the genes and DNA copy themselves. Genes are found in separate strands
of DNA called chromosomes.
We inherit 23 pairs of chromosomes and one member of each pair comes
from each parent.