cancers are genetic because the origin of the cancer involves changes at the
basic gene level of cells. Some people have either genetic
inheritance of a mutation (in the family) or exposure to cancer-inducing agents
(carcinogens like ultraviolet light or cigarette smoke) and are at higher risk
of developing cancer.
human genome, or “master blueprint” of human genetic potential, consists of 23
pairs of chromosomes; one set from each parent. A chromosome is a single DNA
molecule which holds the code for all characteristics and is contained in the
nucleus of every cell.
are the smallest functional units of the inherited information in DNA. Because every
person inherits a set of chromosomes from each parent, different versions of
genes, called alleles, may be present. Whether or not a trait is seen depends
on if the trait is dominant or recessive. Dominant traits show up (are
expressed) even if only one allele is involved. Recessive traits require both alleles
to be involved in order to be expressed.
cancers are sporadic and caused by several acquired (not hereditary) changes or
mutations. A small percentage (5-10%) of cancers are inherited and often passed
from one generation to the next in an autosomal dominant pattern (every
generation, men and women, are affected). Even having a mutation, however, does
not guarantee that cancer will develop. Cancer is a multifactorial disease in
which environmental factors and genes interact to cause its development.
“red flags” for hereditary cancer include: early age of onset, bilateral
disease in paired organs (breasts, ovaries, etc.), multiple primary cancers in
the same individual, multiple cancers across three generations, clustering of specific
tumor types, and Ashkenazi Jewish heritage.
is genetic testing right for you and your family? Your health care provider and
a genetic counselor or oncology nurse with specialization in genetics can help
you decide. Ethical issues involve the impact of testing and results, who and
when to share testing results with, and purpose for the testing information. Economic
issues, including the cost of testing, can be significant – about $3,000 for a
comprehensive series - as many insurance companies cover some portion of the
testing, but not all. Practical issues include timing, treatment and
surveillance decisions, and testing of children or siblings. Individual
emotional responses can be unexpected and may result in a sense of guilt, or
recognition that not everyone in the family wants the same information. All
these issues warrant careful consideration. Only you can make the decision about
testing with appropriate information, time, and support.
learn more about genetic counseling and testing, visit these helpful websites:
Kerber, MN, APRN, ACNS-BC, AOCN, APNG is an advanced practice nurse in genetics and works as an oncology nurse specialist with Georgia CORE - the Center for Oncology Research and Education. You can reach Alice via email at firstname.lastname@example.org.![endif]-->!--[if>![endif]-->!--[if>![endif]-->!--[if>![endif]-->!--[if>![endif]-->!--[if>![endif]-->!--[if>![endif]-->!--[if>![endif]-->!--[if>![endif]-->!--[if>