History
editThe Hereditary Cancer Program (HCP) was founded in 1996 by a combined effort on behalf of the BC Cancer Agency (BCCA) and the B.C. Provincial Medical Genetics Program. [1] Staffed by pathologists, oncologists, genetic counselors and medical geneticists, the HCP is dedicated to educating health-care professionals, as well as providing “information and genetic counseling for individuals and families with a strong history of cancer” [2] . The main goals of the HCP are to “increase the effectiveness of genetic testing by focusing its use on those individuals and families for whom it is most likely to be informative” and to reduce the utilization of unnecessary medical procedures and the attendant anxiety (such as intensive screening, testing, and surgery) by accurately identifying mutation carriers and non-carriers within families”. [3]
What is Hereditary Cancer?
editMain Article: Cancer syndrome
While anyone is capable of developing cancer, the cause of most cancers is not due to a hereditary risk. [4] In fact, it is estimated that only 5-10% of all cancers are a result of inheriting genes mutations [5] [6]. Some common hereditary cancers include breast cancer, ovarian cancer, hereditary nonpolyposis colorectal cancer and hereditary intestinal polyposis syndrome (Peutz–Jeghers syndrome). Hereditary Cancer usually develops at an earlier stage in life than other forms of cancer and is caused by changes (or mutations) in specific genes which are passed from one blood relative to another. [7]
- You are at risk of Hereditary Cancers if:
- 2 or more closely related family members with the same type of cancer
- A pattern of cancer over at least 2 generations runs in your family
- Blood related family members had cancers diagnosed at an earlier age than expected in the general population
- Multiple primary cancers in an individual
- An unusual clustering of cancers in you or a blood relative
- A pattern of cancers associated with a known hereditary syndrome runs in your family[8]
- You are at risk of Hereditary Cancers if:
Genetic Counseling
editMain Article: Genetic Counseling
A genetic counselor is a medical professional who has had special training in the field of medical genetics and counseling. Genetic counselors are trained to help families distinguish their susceptibility to inherited disorders and assess their risks of possibly passing on gene mutations to their children. [9] At the HCP, “The goal of genetic counseling is to help people to learn more about hereditary forms of cancer and to understand their own risk of developing cancer”. [10] HCP genetic counselors will determine what options are available to your family, whether genetic testing is available, and what would be the best possible index case for your family.
Genetic Testing
editMain Article Genetic testing
Mutations that cause hereditary cancers are frequently initiated by changes of a single DNA nucleotide within a specific gene on a specific chromosome. [11] We do not know yet, why these changes or mutations happen, but we can still detect a mutation, or predict if a mutation could happen by genetic testing. Genetic testing examines an individual’s genotype (their genetic makeup) against that of a gene database, looking for one or more Single nucleotide polymorphisms (SNP) in specific genes that could cause the gene to stop functioning correctly, and thus lead to abnormal cell growth.
If the HCP’s genetic counselors decide that genetic testing would be useful to you or your family, they will proceed with either index testing, usually given to a family member with a type of hereditary cancer, or carrier testing, to examine if your family members also have the same gene mutation that is already confirmed in the family. [12] HCP’s Genetic counselors will guide you through the process and help you interpret your results because the process is lengthy. There are, after all, believed to be around 20,000 - 25,000 genes in the human genome. [13]
External Links
edithttp://www.bccancer.bc.ca/PPI/Prevention/Hereditary/default.htm -- BC Cancer Agency
http://www.bccancer.bc.ca/default.htm -- Hereditary Cancer Program
References
edit- ^ Williams-Jones, Bryn (2002). Genetic Testing for Sale: Implications of Commercial BRCA Testing in Canada. University of British Columbia. pp. 7–9.
- ^ "What is the HCP?". Retrieved 12 December 2012.
- ^ "Hereditary Cancer Program Goals". Retrieved 12 December 2012.
- ^ "Hereditary Cancer Program". Retrieved 12 December 2012.
- ^ "Hereditary Breast and Overian Cancer". Retrieved 12 December 2012.
- ^ "Familial Cancer Sydromes: Information from Answers.com". Retrieved 12 December 2012.
- ^ Lu, Karen. M.D.,, Arun, Banu. M.D. "Clinical Cancer Genetics Program". Retrieved 12 December 2012.
{{cite web}}: CS1 maint: extra punctuation (link) CS1 maint: multiple names: authors list (link) - ^ "Assessing Family History". Retrieved 12 December 2012.
- ^ Canadian Association of Genetic Counsellors. "What is a Genetic Counselor". Retrieved 12 December 2012.
- ^ "Genetec Counseling and Testing: BC Cancer Agency". Retrieved 12 December 2012.
- ^ Johnson, George (2006). The Living World. St. Luis, Missouri: McGraw Hill. p. 194.
- ^ "Genetic Testing". Retrieved 12 December 2012.
- ^ U.S. Department of Energy Genome Program. "How Many Genes Are in the Human Genome?". Retrieved 12 December 2012.